Lazy Web, O' Lazy Web...

Help me O’ Lazy web find a free hosted web based email app that runs on Free Software and has a reasonable terms of service agreement? A recent discussion of the proprietary nature of some web apps has me rethinking my beloved google web apps, thus the new wordpress blog I’m trying out. Now I’m looking for a replacement for gmail, I’d like it to be open source and have a reasonable TOS agreement, no scanning my email for ads, no rights to everything I write, accessible from the web and free of cost. While i’m at it I’d like the moon on a stick.