Where is that email? Ask ZOË!

For a while now, I've been using Zoë, even though it is still in beta.

It's great, it enables me to search through all my emails from all of my accounts at the same time. But wait, there's more! Zoë reads RSS feeds so I can archive and index a lot more than just email. (This Weblog for example.)

Description from the Zoë website:

"The goal here is to do for email (starting with your personal mailbox)
what Google did for the web... The Google principle: It doesn't matter
where information is because I can get to it with a keystroke.
So what is Zoë? Think about it as a sort of librarian, tirelessly,
continuously, processing, slicing, indexing, organizing, your messages.
The end result is this intertwingled web of information. Messages put in
context. Your very own knowledge base accessible at your fingertip. No
more "attending to" your messages. The messages organization is done
automatically for you so as to not have the need to "manage" your email.
Because once information is available at a keystroke, it doesn't matter
in which folder you happened to file it two years ago. There is no
folder. The information is always there. Accessible when you need it. In