Via the Freshmeat feed, I just noticed this thing called the "MinGW cross compiling environment" that looks like it does more or less the same thing as my xmingw overlay, except that it's not distro-specific. (It's not my fault that the portage concept is awesome.) I took one look at the mercurial repository, and found that it consisted of exactly one shell script. Wow. It's a big one, too. It currently supports 26 packages and is roughly 2000 lines long. My overlay, on the other hand, supports over 200 packages (with at least one shell script per package), and I probably don't want to know how many lines of code that is. I'm surprised that the number is over 200. Well, sort of. Its Bazaar repository is currently on revision 466, and apparently I've had this branch for a little over a year. That latter part's news to me.
In related news, as I type, I'm building Firefox 188.8.131.52 via xmingw. The Windows XP machine that I use is going loco, and many programs (including Firefox) crash when I try to use them. Strangely enough, my self-compiled version of Pidgin runs just fine. So, in that spirit, I'm trying to see whether a self-compiled version of Firefox will do the trick as well.