Attention span of a ... ooo shiny!
I had been working on the background for an "Ultimates" version of an old campaign, when I got an idea while reading the current issue of Uncanny X-Men (467). The gist of the idea is that the Phoenix Force grabs characters (the PCs) from different campaign universes (and probably alternates of those... alternates that met with a not too happy fate) to have them intervene in the events of said issue.
It's probably because I've been enjoying X-Comics again the past few months and I've particularly enjoyed the last couple of issues of UXM. That, and for me running a campaign in the Marvel 'verse is pretty easy.