An
interesting link that went out recently on one of the mailing lists I watch... It's basically a how-to for at-home electrolytic rust removal.
Looks useful for smaller, easily handle-able parts; I may try it over the winter when I have the control arms out for bushing replacement (no compressor or sandblaster... yet
). Larger parts such as engine cradles could likely be done easily using a kiddie pool and an iron electrode of a suitable size.
Engine blocks, space frames, and other odd-sized/shaped items could be done using a truckload of washing soda, and your neighbour's in-ground pool while they're away on holidays.