To clean my chain quickly while it's still on the bike, I like to use Simple Green. It's pretty cheap and works great. I dilute it in half and use a rag and a toothbrush to clean off the chain and cogs. Then, I just wipe it off with a clean rag, apply Pro Link (my favorite lube), and go for a ride. It's amazing what a clean chain will do for your attitude. I got a Park Tool cleaning kit for Christmas. Can't wait for the snow to melt so I can try it out.