http://plagger.org/trac
Plagger is like pipes for news feeds. You can read feeds from almost anywhere and output them to almost anywhere. It's written in perl.
http://validator.w3.org/feed/
The feed validator from W3C. Checks either a URL or pasted code.
http://www.chrisfinke.com/wordpress/plugins/feed-statistics/
The Feed Statistics plugin does exactly what it says on the tin, gives you stats on your feeds including subscribers, link click throughs, etc. It seems to do what Feedburner offers.
