I've done a few breakouts but really only because some sets I like to enjoy in a binder and to do that, I gotst to free the card from the giant clunky slab they're in.
For SGC and PSA, my method is simple - position a butter knife right on the seem between the top and bottom portions of the slab. It helps if you position it over that little notch in the center where there's just a wee bit of additional space. While holding the knife and the slab in one hand, take a hammer and tap at the end of the knife handle until the blade pops between the two halves. (There will be a satisfying *crack* once this happens) After that, I set the hammer down and move the knife around the sides of the slab without ever getting the knife anywhere close to the card. Usually, after I move it down one of the sides, the entire slab falls apart at this point freeing up the card.
Hope that makes sense!
