Halloween

Halloween is around the corner and I am thinking of doing something this time. The only problem ... well, I don't have any ideas for costumes and I don't intend to buy one (they rarely fit well and there is hardly any fun in buying one).

So ... any ideas ? Here are some things I came up with (some might not be original) :

1. BSOD/Kernel Panic: Interesting. Geeky. Something that few people would understand.
2. Robin Hood: 'Ah' to being a fan of old school heroes (make it "older" school).
3. 404 Not Found: What scares us, hypowebiacs, the most.
4. Windows v8: I have some interesting ideas here, but I need to think more.

Any other ideas ?