Have you tried Fluid?
If you haven’t tried Fluid, yet, you should. With it, you can wrap web apps in their own standalone Safari-powered browser. This way, the applications will live in your Dock just as a regular app would do. You’ll be able to close your browser, but still have a look at your favourite web apps.
The app is free and runs only on Mac OS X. If you’re on Windows or Linux, you can check out Prism which is similar to Fluid, but developed by Mozilla.
16bugs is a great candidate for a dedicated app, so here is an icon you can use with Fluid. :)
