Here’s marginaali excerpt, a tiny WordPress plugin I wrote to emulate the output of the_content_rss with the_excerpt. I was using the_content_rss to produce more compacted excerpts on my front page, but then I began to develop something of a profanity filter, and wanted to apply it to all content my front page, but not the feeds, so I had to resort back to the_excerpt.
As you can see, it’s a pretty specific use, so it’s very unlikely that you should find this plugin useful, but I had to archive it here for my own use and just in case anyone else should have any use for it, here it is.