I recently had to wrap a gift for a person and occasion that I didn't know (a buyer requested a gift-wrapped Nautilus bottle opener), and had this problem: all of my wrapping paper seems to be themed. That is, it's "birthday" or "baby shower" or "winter" or "Christmas" - no all-purpose, generic wrapping paper! (I ended up using a red-and-green paper that didn't look too Christmassy.) And then I saw this advice from Erin on Unclutterer: use silver. And it's true, there's no situation that I can think of where silver won't work - and it can even be themed with ribbon color choice, like red/green for Christmas or pastel colors for babies. Sounds like a very usable supply to keep around!