Just noticed that my local supplier of cheap electronic toys (Maplin
- like Radio Shack, but in the UK) is offering digital camera PSUs. These are the typical adjustable voltage wall-warts, but they can supply up to 2A, which is usable for de-rusting. Cost is £15, which is expensive for a cheapskate recycler like myself, but cheaper than the $50 someone recently quoted.
Mind you, I think £15 must be nearly $50 by now, with the way the dollar is collapsing.