Has anyone ever actually used a tower shield in game?

IMO the rules the tower shield are completely unfair.

Not only do you have a penalty on your attacks, there is a maximum dexterity bonus, and a HUGE armour check penalty.
Even if you have a darkwood tower shield; the only real benefit you get is that it is 23 lb instead of 45, and the check penalty is -7 instead of -10.

I keep wanting to make a legion type character, but can't justify to myself to actually use a tower shield. :/

I have used a tower shield a couple of times in Pathfinder. Usually, I use it to close the distance between myself and some ranged opponents. There is a fighter archtype that can use tower shields without all of the penalties (he still had massive one since he had a tower shield and plate armour), and I made a pretty good guy who specialized in it.

In Pathfinder, the tower shields give a +4 AC for an armour check penalty of -10. The upside is as a standard action, you can block off one side of your square, and no non-magical attacks can hit anything behind the shield. The tower shield champion archtype reduces the and can get bonuses to saving throws against some magic guys. As it says on the Pathfinder SRD I use, the tower shield isn't much good out of a battlefield, or if you only want to have AC and hp.

I assume that for legion character, you are referring to the Holywood portrayal of the Roman armies, with the Lorica Segmentata and Scuta tower shield. Roman tower shields were pretty much ineffective in one on one fights, not that their training was really guided towards that either, so they would often use slightly smaller, ovular shields in battle. Though those shields could still be tower shields, you could also count them as heavy shields. And if you really wanted to, you could count the Scuta as a heavy shield, keeping the tower shield look for aesthetics.

EDIT: I have personally done a bit of work with tower shields. They are very encumbering, and I wasn't strong enough to do anything but duck behind it (since it was a ...Pavice I believe is the word) tower shield. It was only good in multiple person fighting, when you had other people near by to protect you from being outmanoeuvred. In a duel, it was ineffective.

It is the hollywood legion I'm thinking of. But I am thinking (it is a higher level character) of having the leadership feat so that I could work a shield wall with my followers.

I however play 3.5 and there aren't those benefits for the tower shield (as far as I know)
It has the +4 bonus, -10 check, 50% arcane, and can be used as full cover when you sacrifice your attacks.

I'm not sure the penalties are so bad for what you are getting (+4 bonus to AC and the ability to gain total cover)... plus the armor check penalty only applies when you are actually wielding it. I imagine most legion soldiers didn't try to swim, sneak, or climb while holding on to their tower shields.

Making the shield of masterwork quality would decrease the armor check by 1. Making it out of mithral would decrease the armor check some more and raise the DEX max modifier.

I think a player and DM could probably work out some feats that would improve the fighting style of using a tower shield. A feat that would allow someone to use the shield to gain cover and attack in the same round, probably with some prerequisites (like Shield Ward, maybe) or restrictions (like you can only attack and use cover when attacking with a spear).

What is the action to draw a shield? In pathfinder, it is a swift action, so you could draw it when engaging, and ditch it later. With a squad of soldiers, it could be more effective since you'd be a line against anything coming at you. Without them, it might be an item more strapped to your back and you take out when acting as cover. Or, just change the look of your heavy shield. That's what I would do without the Tower Shield specialist class.

Tower shields are wooden. (I would hate to try and lift a steel one) But even making it out of Darkwood the check penalty would be -7 instead of -10.

If the DM would be willing to make/allow the feats then that would be one thing. But going by book rules.... IDK.
But a legionary probably would try to sneak, hide, balance, move silently, etc. with his shield.
If you will need it you aren't going to leave it behind.

Yeah, maybe see about getting some feats. It could make the tower shield much more useful in combat.

You could also strap it to your back. The penalties disappear (minus the ones from weight) if you do that.

What I am saying is that a legionaire would not swim, sneak, or climb... he's a legionaire. What he does is wade into a battlefield with his shield buddies and kick butt.
That's what he's bred to do.

What I am saying is that if you choose to play a legionaire, you are saying yes to somethings, and no to others. Can you make a decent legionaire fighter using a tower shield? Sure... though, like every game, it depends on the type of game you are playing... and a little bit on the make-up of the rest of the players. The legionaire character (game mechanics wise) is a pretty specialized fighter.

I personally have never played much of the front line, so I haven't used a tower shield, though I have seen them used in my games to great effect. However, a quick browse of the rules has shown me that one of the things that made them so useful was a house rule my DM had, that you could plant a tower shield, and have it basically be a place where tanks could drop the shield for others to have cover, and let them then take the fight to the front line.

The other thing that one of the fighters I played with had was a tower shield that was enchanted with the animated property, so he got to still wield a two handed weapon and have the benefits (and drawbacks) of a tower shield.

I found a brief written example of the house rule on "giants in the playground" if you want to look it up, but I haven't seen any official rules on it.

It would appear that the Roman Legionnry would in fact use their shield as a punching weapon... though the 3.5 Tower Shield does not allow it... so, three options, I suppose:

1) Use the Heavy Shield instead of the Tower Shield, and just call it a Scutum. This would seem like the simplest solution. While you lose the extra +2 AC and the option to use your shield for (limited) total cover, it does allow you to use the Shield feats without having to bend the rules. If I were to be making a Roman Legionary character, I would likely go this route. One feat to check out would be Shield Block, which allows you to deflect one missile attack per round, making your heavy shield more like a tower shield

2) Use the Tower Shield, and only pick up the defensive Shield feats, like Shield Specialization, Shield Ward, Active Shield Defense, Shield Wall, and the tactical feat Formation Expert. You can't punch with a tower shield, which is unfortunate... but if you love it, then who cares. As he advances, I'd probably look at getting him mithral breastplate and mithral tower shield.

3) Bend the rules or add to them. Create an additional Tower Shield Bash feat which requires Improved Shield Bash as a prerequisite. Or allow the character to make bash attacks if they have a STR of 15+.

I'd say it looks like they are using heavy shields.

... having just watched Centurion, I find it interesting that, as soon as their legion is decimated, they all drop their armour and shield

Here's an idea for a Roman Legion soldier... well 2 soldiers actually. This character really only works if he has a friend with at least the Phalanx Fighting, Combat Reflexes, Vexing Flanker, and Adaptable Flanker feats. That's the core bit of the pair, after that you could take it a bunch of ways... charging mixing with a bit of Barbarian for Pouce, two-weapon fighting (shield/sword) mixing with a bit of Rogue for sneak attack damage to flanked foes, locking down enemies (like the example below), etc

The basic tactic is the pair moving together, stand side-by-side which gives them bonuses to AC (with Phalanx Fighting), causing them to flank their opponents (with Adaptable Flanker) which gives them bonuses to attack (with Vexing Flanker).

The rest of the build revolves around them attacking with both shield and sword, defensively fighting with combat expertise (vexing flanker offsetting the attack penalty, deadly defense adding to damage), and messing with any enemies that provoke attacks of opportunity. The Stand Still, Defensive Sweep, Double Hit combination is fun -- enemy tries to leave, you stop them from moving; enemies hasn't moved by the beginning of your turn, you get to attack them freely twice. Good times.

ABILITY SCORES
At Level 1: STR 14, DEX 15, CON 12, INT 13, WIS 10, CHA 8
At Level 20: STR 16, DEX 18, CON 12, INT 13, WIS 10, CHA 8

FIGHTER 20
Lvl 1: Phalanx Fighting, Combat Reflexes, Able Learner
Lvl 2: Two Weapon Fighting
Lvl 3: Vexing Flanker
Lvl 4: Adaptable Flanker
Lvl 5: --
Lvl 6: Shield Specialization, Improved Shield Bash
Lvl 7: --
Lvl 8: Improved Two-Weapon Fighting
Lvl 9: Shield Ward
Lvl 10: Combat Expertise
Lvl 11: --
Lvl 12: Robilar’s Gambit [PHB2], Double Hit
Lvl 13: --
Lvl 14: Stand Still
Lvl 15: Defensive Sweep [PHB2]
Lvl 16: ACF - Overpowering Attack [PHB2]
Lvl 17: --
Lvl 18: Active Shield Defence, Deadly Defense
Lvl 19: --
Lvl 20: Armor Specialization (or Allied Defense)

Equipment: Breastplate, Heavy Shield, Short Sword, Short Spear, Dagger, Javelins (x3)

Equipment Upgrades: Mithril Breastplate +x; Mithril Heavy Shield +x with Bashing +weapon enhancements that add to damage; Short Sword +x with enhancements that add damage

Build Requires: Heavy Shield, Short Sword, and a partner with Phalanx Fighting, Combat Reflexes, Vexing Flanker, and Adaptable Flanker

I may have missed this But was this a specific class or one you just made up?

I used the 3.5 basic Human race and Fighter class for the build above. The feats are from the following books: PHB, PHB2, CWar, and maybe the Miniatures Handbook.

After searching most of the books for feats/classes that interact with shields, I would agree with you that Tower Shields seem next to useless in 3.5. Very few of the feats actually intereact with a Tower Shield and, more specifically, from a 3.5 "rules as written" perspective, the rules seem to think Roman Legion soldiers were using a "Heavy Shield". Meh...

I find the fighter to be pretty underpowered compared to most of the other classes, so, as I DM, I'd likely house rule a bunch of things for the fighter anyway (like giving them the ability to move and full attack)... or use the Tome of Battle classes in place of the Fighter (Warblade, probably being the closest).