They can go all the way up to large bolt-on terminal size. The one in question was about the size of an M-80 firecracker. Made about as much noise, too.
Capacitors can be quite scary. Im much more fearful of capacitors then a CRT. Everyone is up in arms on CRT disclaimers but if your worth your salt and remember your safety training they are no different than working on anything else. No CRT has ever sent me to the hospital.... but capacitors have.
Is that you? Thats a spectacular shot. Tantalums normally just make my heart skip a beat when they catastrophically short.. but these are fantastic photos.
I had such a failing in a Commodore 1541. They can blow up like fireworks. However, it looks more spectacular in his shot because it was a video and hence the exposure time was rather long. It's nothing like that in real life. Just a pop and a flash followed by some smoke. :D