I love Gmail.
It's true. I can't believe I'm actually using Gmail for 98% of my mail viewing and replying now. The speed is great, especially on the searching, as well is the way they handle the threads and conversations. If you don't have an invite yet, find a friend who has one, or spend a buck on ebay and buy one. (They used to cost 30$ and more but now the market is a bit flooded.)