The heat softens the adhesive but take care not to damage the item with excessive heat. It's also commonly available in many households. If you think I'm kidding about its effectiveness, just try it sometime on some tape residue or the like. I was once visiting friends who have horses, and one of the horses had been rubbing up against a pine tree which was oozing sap. She was distressed that she would have to cut the horse's mane off to get rid of the matted, sticky mess.
Epoxies resist almost everything but epoxy strippers are available from industrial suppliers.
These organic acids are caustic and must be used with great care. Spot removal of epoxy may be accomplished by chipping or using the tip of a soldering iron. Be prepared for a bad smell. Someone suggested paint stripper but I have not tried it. Most silicone rubbers may be removed by applying ethyl alcohol to the interface.