Rest. Rest is the obvious one. There are beds, food, and drink here.
But you can spice it up by offering small XP rewards for trying the house dish or the speciality drink. Perhaps = coin spent. Exaggerate some feature of normal cuisine and go over the top with it: the cruelty of veal, the mushiness of mashed potatoes, the spiciness of chili, the size of the biggest hamburger you've ever seen.
If you're in a big city and want to encourage them to take a tavern as a home base, you could offer XP only for items from this tavern.
Or more likely they'll pick a favorite anyway, no need to incentivize. If you want the fiction to exist, just be sure to ask what they're having and present interesting options.
Rumors. Learn of rumors by eavesdropping, chatting people up, or asking the bartender.
The procedure for doing this is: just ask if they're looking for rumors. If so, dock them time and money: that's what they're doing this city turn.
Then generate the rumor. Then decide what source best suits it: eavesdropping maybe. Then transition into the fiction: "You're sitting at the table—what are you having, by the way? The neon pheasant? Then you hear a heavyset fellow with a beard like a waterfall of pitch mention sonething about that cult getting more pushy. What do you do?"
In that example, the players might fail to get the rumor. But other times you can just say, "you heard some folks talkin about the Marseltons: they just up and abandoned their mansion—probably lots of loot still there for the taking."
Minigames. These are fun diversions. If you're playing face to face, let the players wager money on things like:
- Thumb wrestling
- Dexterity games
- Paper rock scissors
- Guess a number
- That hand slapping game
- Liar's dice
- Dice tower building
Either (a) always generate their opponent and play the person up, or (b) just use skill checks until the player misses: a miss indicates a worthy opponent; generate her now and actually play out the game.
These opponents can turn into allies or enemies, and you've already got some shared history.
Bards. Bards spout lore, usually unintentionally. Check to see if there's a decent bard playing. 1/6 of the time, yes, and he's spouting lore in his verses. Generate the bard and his lore according to the procedures detailed elsewhere or upcoming.
Bards always need something: fame, money, drugs, love; and if you can help then out maybe they'll go on tour with you and tell of your exploits.
Describing a tavern. Give it a name if you must, then describe one unique thing. Like a bunch of goth teenagers hang out here because the drinks are all red and black.
Or just make them boring. That's fine too.