OMG! I just adore mantis shrimp. My brother in law had one, some years ago.. He was worried about it cracking his tank, as it was a hitch-hiker in some live coral and he hadn't planned on it, lol.
They've actually tempted me to want to try a salt tank, just so I can have one.. Are the ones in the pics actually yours, Hallyx? if so, I am extremely envious! (of both shrimp and photography skills!)