My Body Glove case broke the day after I got my Evo... right on the thin part by the volume controls. Sprint got me a new one, thankfully. Nice case, but nearly impossible to remove.
It's pretty easy to take off actually. Take a penny or a dime and stick it in that slot in the lower right hand corner and twist. The case will pop loose, now just separate the rest of the lower part of the phone (by the capacitive buttons), then lift the phone up out of the bottom part of the case, this will disengage the top part from the bottom part and the phone is free again.