Ask HN: Where to get a ML for my open-source project?

I'm trying to create a mailinglist for GitX, but I can't really find a good place to create one. There's Google Groups, but I don't like its interface, and it does weird things with fixed width input. It also shouldn't line-break stuff like patches that are >80 characters wide. I'd like it to be as open as possible, so no need to register to post, and preferably an easy registration process, like just entering your email address, or subscribing by sending an email (like mailman does). I don't really want to host this myself, so I'm looking for a hosted solution, which should be free. It'd be nice if it had some support for this workflow, but shouldn't get in our way. That means it just should stay a mailinglist, but optional stuff like (inline) patch syntax highlighting etc. would be nice. It would also be great to have a spamfilter working on the web interface. Anyone know of something that we can use? Google Groups seems to be the big guy here, but I don't really like it. Things like SourceForge allow you to host a mailman-like mailinglist, but I'm looking for something of this century.