A couple of years back I did my first bard in 3.0 in a thieves campaign. His specialty?
Perform(puppetry)
His concept was that he was a traveling con-man/snake-oil salesman who worked out of a customized wagon which usually doubled as a puppet stage (the kind where shutters open up on the side of the wagon and you see the puppets). He would often park in the town square, climb into the back, throw open the shutters, and start performing a Punch'n'Judy stage show for passersby (which more closely resembled Triumph the Insult Comic Dog in content ). His primary source of income was grifting locals out of their money through Bluff and Disguise, or, if the police were a little too suspicious, just as a traveling performer.
His highest skills were in Bluff, Disguise, and Perform, which are surprisingly easy for a bard to get up to obscene levels. His "masterwork" wagon also was built for easy disguising, with fold-down panels that could be quickly rotated out, so that the wagon might enter town bearing signs saying "Wong's Laundry Service" with the bard as an old woman driver, but then duck into an alley and come out a short while later with the wagon saying "Monk Ale" and the bard as a young bald monk driving it.
In combat, he could whip out the puppets (i think he had quick draw) and use them to make sarcastic comments about the enemies, which counted as his version of inspire courage, etc.
Min-Max Note: You can really crank up Bluff to scary levels as a bard, and you can reach a point where it gets outrageous even at mid-levels, especially when combined with Diplomacy. Consider this:
Bard, level 10, 13 ranks (+13)
Charisma 24 with Eagle's Splendor (+7)
Persuasive feat (+2)
Skill Focus (+3)
Glibness spell (+30!!!)
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Total Bluff +55
Mature Adult Black Dragon (CR 14) sitting in his lair. 25 ranks in Sense Motive (+25)
Wisdom 15 (+2)
"The bluff is way out there, almost too incredible to consider." (+20)
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Total Sense Motive: +47
The bard could walk into the dragon's lair and say something like, "Hey son! It's me, your mother! I got to fighting with this wizard last week and he had an artifact I didn't know about, and wouldn't you know it, he polymorphed me into a human and stole all my gold. So I'm just stopping by to borrow some cash from your pile here so I can run into town and have this sorcerer I know polymorph me back into my own form. No, don't get up. Look, I'll just take this pile of gems over here and I'll be back next week to pay you back. Oh, and your father says hello. Alright, see you later!"
And as ridiculous as this sounds, the bard has at least a 45% chance of it working. And if the bard is not greedy, and maybe he just goes in for a small portion of the dragon's loot, like say, a particular magic item, then the dragon only gets a +10 for suspicion instead of +20, and now the bard has a 95% chance of successfully robbing a creature that is 400 years old and 4 levels higher than his CR, alone, with no help from the rest of his party.
House Rule Note: In our original reading of the Perform rules (in 3.0), every rank in Perform not only gave you a +1 to that skill, but also allowed you one additional "form" of Performance. Hence, if you had 5 ranks in Perform, you had a +5 in five different kinds of performance, such as singing, lute, dancing, etc. Personally, we still use this rule because it encourages people to put ranks into Perform (and to occasionally pick an odd form of performance like puppetry) and doesn't seem to unbalance anything. We don't allow the same thing with Craft, but for Perform it seems fair.