I'm working on an extension that will show you which extensions to use on sites that you visit.
Currently not sure how to get a good quality database done. There are thousands of extensions. I'm scraping the Chrome extension site to get an initial list, but it looks like it will need some serious curating. Probably need to enlist some help on this one.
On the mailprop project I've had some signups to the mailing list, but so far haven't pushed any posts to the list. Still trying to come up with a better way to get signups. It doesn't seem very scalable to go to industry events or contact industry members directly. As a test I started from the promotional products industry. Bought google adwords on related terms, trying to address people in that industry through those. It's not working, since I don't believe people in these industries actively search for these terms.