Ohloh (http://www.ohloh.net/) aims to be a directory of open source projects and developers with a social aspect. You can search for open source projects or members of their team. Each project can register one or more source code repositories (called "enlistments") that will be crawled by Ohloh. This enables Ohloh to display statistics about the project, like how many lines of codes are found in each language, how many contributors exist and a history of commits. It also makes evaluations like how well-commented the code seems to be. Most interestingly it performs a heuristic calculation to evaluate of much is the code base worth. In case you wonder TYPO3 is evaluated at more than $5,000,000. Yes, that 5 millions dollars! Tell that to your clients the next time they complain about the cost of open source software.
You can also register yourself as a developer. In your profile you can say that you work on such and such project that is also registered with Ohloh. You will be asked for your committer name and Ohloh is then able to find your contributions to the project. You can also just say what pieces of software you use: you can define one or more application stacks to show others which are your preferred open source tools. It's also possible to pat each others on the shoulder by exchanging kudos.
On top of that, Oholoh provides a number of widgets which you can embed on your site, which is a nice way of showing what you're up to and how good you are at it (or at least how active you are).
I tried to register the TYPO3 v4 extensions source repository from Forge as a whole but it proved too large and complicated for Ohloh. It was finally decided to use it for specific TYPO3 v4 subprojects. So I encourage you to register yourself and each of your extensions as separate Ohloh projects to create more buzz around TYPO3. To enhance the buzz, please tag your projects with the following keywords: "typo3", "forge", "extension" and "t3x".
Of course you are perfectly free to ignore the above and I certainly won't come after you and complain. But it's a good opportunity to make some noise about TYPO3, your extensions and yourself.
And don't forget to add TYPO3 to your application stack!