This wouldn't be that hard. You'd have to host Gecko (look to Camino for hosting Gecko in a Cocoa environment) and hook the Dock. That's about it.
Also, you can use the Gmail notifier. You'd just have to hack the JS inside the XPI (which is just a zip file with a different extension). I'm sure it's just a matter of pointing it at a different domain.
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Also, you can use the Gmail notifier. You'd just have to hack the JS inside the XPI (which is just a zip file with a different extension). I'm sure it's just a matter of pointing it at a different domain.