The game might be a few months old now, but Portal 2 will still make for an amazing Christmas gift. And here's hands-down the most clever way to wrap it. Just keep the giftee off the internet until Christmas morning.
It's not going to guarantee you an A+ like showing up with a working portal gun would. But you can still wow your teachers by building your own version of Portal 2's potato-powered AI, even though the kit's a fraud.