I've made some measly contributions back to the Open Source community, mostly to Ruby on Rails (I'm the 24th top contributor to Rails as I'm writing this on 22 Dec 2009, and have also won a monthly Rails Hackfest). I've also contributed patches to jQuery (via Sizzle), Thin, Merb, curb and Homebrew. I wish I had more discipline to roll out polished Rubygems, but I don't so my only published Rubygem so far is Facon, a lightweight mocking and stubbing ruby library.
I also wrote Firefox Secrets (yes, a book on the Mozilla Firefox web browser) in 2005 before Firefox 2 was released. I'm fairly surprised at the few positive reviews on Amazon - if it sold more copies I'd be swimming in my hundreds of dollars in royalties. And yes, I do love Firefox, I think it's the best web browser despite some of its flaws.
I work for Wego.com with some of the brightest people in Singapore trying to build a great travel meta-search engine for Asia and Australia (and one day, we will conquer the world).