This morning while trying to close a firefox tab I accidentally hit a button on Gmail that made it magically faster and better. I'll share it with you: look at the top right hand side of your gmail screen. Look for the link that says "Older version":
Click on this. Boom, magic. You'll find suddenly Gmail is significantly faster, more responsive, and less prone to reducing FireFox to a groaning heap of ooze.
This is awesome. I'm not sure why Google is not publicizing more, and I can't wait till they roll it out more widely. Perhaps it's in beta.