J.Higgins 

I applaud your ingenuity, Zandy. I got to say that the shine on that derailleur is pretty nice! Not all soaps are equal, so could you tell us precisely which laundry soap you are using? My wife usually gets the liquid kind, and I am wondering if that works just as well.

I also forgot to add that over the years, I've done some experimentation with this sort of thing. I've done part cleaning with vibratory tumblers - many of which I have built myself. I've done loads of ultrasonic cleaning. I even was into cleaning motorcycle and bicycle parts in a typical household kitchen dishwasher, of which I picked up for free at the dump. The cleanest results came from the dishwasher, using dish detergent, but it does make any un-anodized aluminum parts grey. I can imagine that the results would be spectacular if I used the laundry soap.