I'll catch some flack for this but I just use a shallow Tupperware container with gasoline. Keep a small fire extinguisher near by, and always way away from any possible ignition sources. Gas works better than any other cleaner I have come across for removing horribly sticky grease and oil.
Let the chain soak for ten minutes, then brush the crap out of it with an old tooth brush. Make sure to wipe the thing down well with a rag, then use your favorite chain lube immediately after.
I would not recommend this with O-ring chains however.