There aren't any class features unique to a Fighter in 3rd/3.5 edition of D&D. The Fighter only gets access to bonus feats as a class feature. I suppose you could look at Fighter only feats, but they're not anything special when you consider what feats other classes have access to that they don't. Weapon Specialization gives +2 damage. Maximized Spell increases all damage from a spell to its maximum. I don't think there are any feats that maximize the damage that a Fighter does when he swings his sword, even just a certain number of times per day. That doesn't mean that a Fighter is useless. It also doesn't mean that a Fighter isn't fun to play. But, honestly, Fighter is a better class to dip into, versus taking up to level 20.