Migrating a wiki from Trac to MediaWiki
I'd set up a Trac installation for wedding planning, instead of using MediaWiki (the system Wikipedia uses, which I already had a couple of installations of) since we wanted both a wiki (venue data, possible honeymoon destinations, guest lists... shut up, it's useful!) and ticket system (useful for tracking things like thank-you notes and being able to assign specific ones to either Liz or myself).
However, Dreamhost doesn't support mod_python, so pages were taking way too long to load. I decided to switch over to MediaWiki for the wiki part and just use my existing Bugzilla installation for ticket tracking. Hence, a new script over on the code page, trac2mw. Our wiki was fairly tiny, so caveat user. I didn't bother having it migrate tickets tickets or attachments, since we didn't have any data there that was worth preserving. The input format, a MySQL XML dump, probably isn't ideal for a lot of people (since Trac runs on SQLite by default.) It does fix up the wiki page syntax (the parts of it we were using, at least), though.