Mozilla Development
I may not technically have "a job", but if you saw me at home, you'd never realize I wasn't just working from home. I've been working with some former co-workers on a project that will hopefully become my next job.
For this project I've been developing in Mozilla. No, not "developing web applications", doing development in XUL, XBL, RDF, and a lot of other fun Mozilla-specific technologies.
Mozilla has a lot of astounding capabilities, as you can see in the book Creating Applications with Mozilla. Mozilla's "XUL" language can be thought of as an extension onto the HTML form elements, including things like menu elements or better layouts. CSS is used in conjunctions with this extension, and XBL allows you to package up various things you can create with the form elements and Javascript into a coherent single unit.