Limited Release
Limited Release by rageprufrock is one of my very favorite X-Men First Class stories (Erik/Charles, of course). I first started reading it on one of the kink_memes and, even while it was still a WIP, I read it over and over again. Charles and Erik are both complete BAMFs in this universe, and their relationship is both complicated and completely awesome. Here's the author's summary: When Alex Summers broke out of supermax to rescue his stupid kid brother, he had no idea it was going to be so fucking complicated. (I believe the story was inspired by a prompt for a White Collar fusion, but it grew into something so much more...)