Hah. I was recently considering the feasibility of making a homebrew CT scanner, only I was thinking of using one of the cheap chinese dental xray machines you can get on ebay for ~$200. (I think I would have probably vacated the room while it was in operation. I'm not saying I don't trust cheap chinese x-ray technology but - well , actually - yes I am...)

Would have required an awful lot of scanning of xray film and would probably only have been able to image something around the size of a walnut.