Tannerite is pretty fun stuff! Its pretty cool to see long range shots easily when you hit the target.
I was at a friends farm down in southern indiana last winter and we put 5# of it in a tupperware container, and put it inside an old consol TV that we shot the screen out of. We shot it from across the field and it threw debris everywhere, almost 50-60 yards away. We also took a dermal and cut a 1"x1" whole in a piece of 4" conduit (buddy is an electrician)... and put a 1# target in there -- that one peeled the conduit apart it was pretty impressive! Took quite a while to pick up after ourselves.
Definitely something to be careful with, but great fun!