Feed 2 Podcast:

http://www.feed2podcast.com/  Input the URL for your blog's RSS feed and presto, you have a podcast!

Feed 2 JS:

http://jade.mcli.dist.maricopa.edu/feed/  Input your blog's RSS feed into this program and you get the java script code to paste your blog's content onto your website, where it will update all by itself!

Del.icio.us Tag Clouds:

http://del.icio.us/  If you have a del.icio.us account, you can grab the RSS feed at the bottom of your del.icio.us page and use Zoomclouds http://www.zoomclouds.com/  to produce a tag cloud.  Del.icio.us already lets you see your tags as a cloud, but if you are using del.icio.us tags to organize the posts on your blog, you might want to produce a cloud from the del.icio.us tags that you can paste in your blog or your website.  Or you can input the feed from your blog into Zoomclouds and get the code to make a tag cloud for the side banner.  How cool is that?