Actually, Shen Mui or whatnot uses soda can machines to advertise for pepsi and others. Being a freely interactive environment, you can actually buy the cans. I\'m sure an equivalent thing can be done for PS taverns... a twist in names is definitely possible. This can allow social interaction with npcs or give a temporary sugar rush simulated by heightened attributes during fights...
Of course, there can also be \"wanted\" posters or posters listing guild quests... something like \"This bandit is wanted... reward of 1000 gold sponsored by the Pepsi Corporation.\" Even though, it would be annoying to have logos pop up everywhere in the game, this is much more preferable than having an extra banner-clicking frame that will not only lag the computer, but make it disruptive to the gameplay.... Of course, if the service requires say 25 banner clicks per hour, maybe it\'s not sooo bad. I\'d still prefer a more subtle approach.
I hope you people manage to pull this off... for the sake of promoting a movement towards free games....
...Working for free... great way to find enthusiastic game creators... I just hope you make enough for sustenance and shelter :p.