I got the silver pantaloons from some guy outside the Copper Coronet. What the hell should I do with them?

You won't be able to do much with them without the golden pantaloons from BG1. Check the ToB forum if you want some spoilers. ;)

Save them along with the golden pantaloons (if you imported or CLUA'd them in). They're part of an Easter egg in the expansion. ToB forum has more details.

sounds like someone's playing Evil PC character ;)

Excellent way to handle the issue of what to include and what not to include in the SoA forum, folks. If we could see this all the time, that'd be great.

Keep them, wear them, show them to your friends.... On second thought, my son got in a bit of trouble for that in preschool. Just keep them.