I’ve been using Postbox (http://www.postbox-inc.com/) for the past couple of months, and I have to say, it’s pretty damn good. 

We use Google Mail for The Escapers, which is great, very reliable and all that, but **** it’s so SLOW. It’s not a Gmail thing really, it’s most websites, the web ain’t ready for complex apps like email yet, or at least, they will never be as good as the desktop equivalent so long as the web has such awful latency compared to the desktop.

Which is why I came to use Postbox, Gmail compatible, it even supports Gmail’s ‘Archive’!

I get a great desktop experience when I’m in front of my Mac, and the Gmail UI when I’m not, perfect.