A buck will buy some pretty cool boy stocking stuffers. Check out these toys that I found at Dollar Tree recently. Your local store should have most (or all) of these items, but if not, you can order them on DollarTree.com, and have them shipped to the store for free. You usually have to buy items by the case when you order through their site, but there are some exceptions on this list.
Metal Model Kits
Light-Up Yo-Yo Balls
Disney Mini-Puzzles in Tins
Licensed Character Pinball Games