If you search on youtube for "Decapping ICs", you will find a post by Applied Science on how to use hot fuming nitric acid to dissolve (destroy really) epoxy. It does involve a dangerous chemical, and he does not take adequate precautions. The worker should wear closed shoes, long pants, gloves, goggles, and a lab coat with long sleeves, and there should be a fume exhaust system rated for corrosive gases and a clear, shatter-proof shield between the worker and the work. Ideally a lab-grade fume hood should be used. This method will do away with most metals and plastics. Semiconductors, gold, glass, some plastics (e.g. teflon) and ceramics should be relatively untouched. The other relatively inexpensive method is a slow, careful grind with a small milling bit in a high-speed drill, like a Dremel or its air-driven counterpart.
Fast methods involve the use of high-power water-jet or laser cutters, both of which are very expensive. Both can take off a finger or put out an eye faster than human reflexes can react. Depending on what you need to know, an x-ray might do the trick and would be quick. Best bet would be to find a x-ray tech, hospital, dentist or vet to do it. Dental and some industrial x-ray machines have very fine resolution.
Mike in California