I bought an HP LaserJet 2300dtn on eBay for much less than usual price. I soon discovered why it was so cheap. A past owner had embalmed the printer in layers of bumper stickers, pogs, labels, and rubber cement. Most of this was removed by the vendor, but I think he just gave up trying to clean up the printer. Much of the glue and goo is still attached to the printer, along with some dirt which helps make the goo more visible.
I've tried alcohol, paint thinner, Goo Gone sticker lifter (citrus power), Oops! remover, WD-40, ammonia cleaner, and 409. All of these soften the gum and goo to various degrees, but leave enough imbedded in the textured plastic surface to make the printer look filthy. I hesitate to try a stronger chlorinated hydrocarbon solvent for fear of destroying the ABS plastic.
Can anyone recommend a favorite solvent or cleaner for sticky goo and gum?