The Papilio One is an inexpensive open source FPGA development platform, which can easily be turned into a fully featured 32-channel logic analyzer. The Gadget Factory sells a logic analyzer "kit" which includes the Papilio One, two 16-channel 5V tolerant logic converters, and probes for about $50. The only thing missing is a case, so here it is!
This is a snap together case. The cover is to be printed on edge, and should be printed with supports to prevent the pin cutouts from sagging. The Papilio should be mounted to the base using four M3 x 8mm bolts.