People who build things inspire me. The things they build often inspire me too. Things like the Maker's Faire make me wish I had a workshop so I could join in the fun (unfortunately my current living conditions only allow for a small closet of tools, and the kitchen table is my best bet for a work surface which would eliminate all of the projects in the following video of Maker's Faire 2011).
If watching that puts you in a buying mood then check out these computer mods from datamancer.net.
Yes, those are all fully functioning PCs