At home I've been using dilute dish soap - Dawn, to be specific, with a "Grunge Brush" to clean the chain. For travel, you could take a very small bottle (from REI, for example) with some dish soap and the old toothbrush mentioned above. Also, dish soap works better than comercial hand cleaners like go-jo, for cleaning up greasy hands and such. I use the Dupont Teflon Multi-lube, which cleans and lubes the chain. 21,000 miles on the stock chain, almost no stretch. Looks like I've got at least another 10,000 miles using this method.
06 DL650 w/all the goodies. Red, the fast one...
04 Honda CRF-250X