Hippo CMS is getting a lot of attention in the Netherlands and around Europe these days, but of course our goal is to make it a world-wide well known product. The only way to achieve that is by promoting it a bit more then letting the product promote itself.
Recently I came across Ohloh. Ohloh is a source directory that helps you find the software product you need. With some help of tags, stacks and the Ohloh community you can find some great pieces of software.
To help developers find Hippo CMS, it has recently been added as a project to Ohloh.