hehe. yeah, just have a spawner in one of the taverns tack an XmlMessage attachment on when they walk by. You can set the attachment to expire after a while to be nice
SETONTRIGMOB/ATTACH/<xmlmessage,*fart*,15/expiration/00:10:00>will add an attachment that will produce the emote every time someone near them moves, with a minimum of 15 secs between emotes. The attachment will expire after 10 mins.