I'v been using citrus degreaser to clean my bikes for years. I usually get a gallon jug of it from the auto parts store, and it lasts a long time. I use it for cleaning the drivtrain, either using a chain cleaner or by soaking the chain overnight. I've used it with a rag to clean the rims. I'll sometimes even use it to scrub a nasty bit of dirt or grease off the frame. However, some of the discussion in this very good question has got me wondering:
Are there parts of your bike that can be damaged by degreaser? Obviously, keep it away from the bar tape or a leather saddle, but what mechanical parts could be harmed by citrus degreaser? Also, are there types of degreaser out there that are gentler and could be more appropriate?