Warning: Some of this may be completely idiotic and/or already suggested.
Here are some of the ideas that I have had for what should be in taverns, mainly in adventure mode.
1: Randomly generated stories told at tables. It would probably have some really nonsensical ones, but hey, the person telling it is probably drunk. Plus, you could find really great ones. Also, you could walk away if you didn't want to hear it.
2: Conmen. These guys would pretend to be quest givers and lead you on to a location where there is nothing but bandits waiting to jump you and steal your money. They could occasionally do cons on you, and give you fake medical stuff for your wounds.
3: Card games or word games. If card games are not possible, then word games at least. They have been around since the 1400s, at least! Again, can be avoided.
4: Bar songs. Occasionally, the bar will break out in song, and if you have a bit of musicality you can get money from your singing! Ideas for particular songs:
Here!5: This is a place where you can find the Mysterious Stranger. He should look similar to any evil/death god who has a human/elf/dwarf form. He could offer you a very special item (Adamantium heart that makes you able to survive without a heart, anyone?) that has one price: Your soul. If you take him up on the offer, he takes your soul. This doesn't affect the gameplay much apart from the animals hating you more then usual, not being able to stand in a church without dying and being at the whim of a death god. Sometimes, he will come back for favors. If you refuse him, he kills you.
6: Drunkards, essentially new versions of
drunks, often hang out here. In fact, they practically live here. Hell, they actually live here. You can buy them a drink and they will automatically join you. They are quite useful for charges, but will never follow your orders or even care what is going on.
7: Informants, shady characters who know about the layout of the nearest noble's house, and you will know too if you give them 40 sliver coins quick. Useful if you want to play the thief for a bit.
So, tell me what you think, and please criticize.