Things that have worked for my bard:
Obscure Lore - If you aggressively make suggestions about using your Bardic Knowledge, and the GM is flexible, then this feat can really pay off. Bt if the GM isn't going to cooperate, then Bardic Knowledge is useless.
Bluff - You can feint sure, but more importantly you can LIE! This one will come in handy if you have a Paladin in the group. With Skill Focus: Bluff and the right CHA boosting items you can tell people the sky is green and get away with it. Don't be afraid to use it on your fellow PC's either, especially if they are mocking you for playing a bard! I took this, and have had frst pick of treasure ever since.
Improved Counterspell - Maybe you can't cast spells as powerful as a wizard or sorcerer, but your caster level is just as high as theirs. Plus, since bard spells cover such a wide range of schools, you make an excellent counterspeller. Especially if you're not acting as a front line fighter. You can stand back and sing, bosting your allies, and ready an action to counterspell. Add in Dispel Magic and Greater Dispel down the raod, and nobody casts spells unless you say they do.
Lingering Song - This is a big help if you want to actually do some fighting too. Spend one round singing, and then let lingering song keep the effect rolling while you get stuck in.
Synergy Bonuses - Bards have access to a lot of skills. Take advantage of that to max out your synergy bonuses. They really add up.
Lyric Spell - At higher levels, there's no way you'll ever use all your Bardic Music each day. This feat lets you convert songs into spells. Very handy.
Use Magic Device - Don't skimp on the levels here. With a maxed UMD, you can use fun toys like a Wand of Fireballs and last away like a sorcerer.
Magic Items - If the GM will let you get them, look for items like a Choker of Eloquence, Cloak of Charisma, or Rod of Splendor. Songblades are great if you can get one.