atom2rss - ASP script for converting an Atom feed into valid RSS.
BlogFeed - Perl script for creating RSS feeds. Includes installation instructions.
FeedBurner - Allows weblog owners and podcasters the ability to manage their RSS feeds and track usage of their subscribers.
News Is Free - A news portal site that offers tools to publish news items to weblogs using the Blogger API. Multi-lingual support. Source code available.
Syndicate - Information on syndicating a page using RSS.