I don't usually promote clothing in this space but this site, Geo-Tee, crossed my desk and I thought they have some cool GISy offerings just in time for the holidays. They've got T-shirts and stickers for the GIS-inclined. Here's what they've got to say about themselves:
We supply apparel for the seasoned old-school GIS’r that was doing GIS with punch cards, to the newbie who just figured out the difference between a datum and a projection.
And frankly, the shirt above, Will Map for Food, may be one I'll need to order in the near future!