+1 for Simple Green. It is my go-to for a general shop cleaner.
Someone mentioned paint thinner jokingly... i'm not tryin to take a dump on the eco topic, but that jogged my memory.
I recently used paint thinner (odorless mineral spirits) to degrease my chain

That sucker was spotless inside and out. Dissolved the built up chain wax completely. I found the cleanest way to do it is to remove the chain and put it in a quart mason jar, dump in some mineral spirits, close the lid and shake it up. May need to repeat with fresh mineral spirits for a second round. Remove chain, wipe dry with a clean rag, blow out with compressed air or let air dry overnight, add fresh lube and its good as new.
Obviously be responsible with mineral spirits. I find that if you let the used stuff sit for a day or two, all the dissolved contaminants settle at the bottom of the jar. Then you can siphon off the clear mineral spirits with a syringe and deposit in a clean jar and re-use. Let the contaminants jar sit with no lid for a few days. The remaining spirits will evaporate and you can trash the contaminants and clean the jar. Maybe not the most eco friendly option, but HIGHLY effective.
This isn't something I would say is necessary very often, most of my chain cleanings only require simple green and a chain brush. But if you get caught out on a rainy day in Pisgah and get that gritty sediment penetrated throughout the pins and rollers, this is a good way to reset and start from scratch.