“ Orcish currency is derived from glass beads. The art of glassworking is well beyond them, but perhaps the orcs have something of value to the civilized races, such as animal pelts, and well made axes, and bows. The humans trade beads for the goods, and the orcs will trade the beads amongst themselves as a form of their own currency. Perhaps they value blood red beads above all others, or animistic orcs favor beads in the colors of their gods.
Inspired by Indian trade beads, some of which could be quite ornate and beautiful. Most North American Indian beads were made in Italy. Surprise!”
“ An army and navy who work in the same way as others except their rank titles are upside-down. So people start as full generals and those with the rank of private command armies.”
“ In a crowded marketplace, a man is standing on a soapbox, orating. Some of the crowd are cheering, some hissing, some standing around saying 'I can't hear a bl**dy word he's saying'. It's a hustings for an election. The PCs can either leave, or stay and listen. If they do the latter, then they can vote too, and they might get quite involved in the cheering. Depending on who wins they might get quite involved in the post-election brawl too...
There are numerous possibilities with this encounter: the PCs might end up talking to one of the nervous candidates before their speech, and offer encouragement and support. Of course this candidate may well turn out to be someone with outspokenly unorthodox views, and the crowd don't take kindly to s/his supporters. Or maybe the seemingly innocuous candidate turns out to be a complete racist, and the PCs wander off embarrassedly, pretending they weren't talking to this person five minutes ago.”