[txxxxd]

Just click "show search options" and enter "Fred" in the from box and "Friday" in the date box.

Much easier than scanning through pages and pages of messages.

[roadnottaken]

That's a fair point. But nowadays OS'es all have good search tools (e.g. SpotLight in OS X) which makes it unnecessary to organize your files ("why organize when you can search"?). However, I still like my files organized so I can browse them to find things in a straightforward way. So, too, with e-mail.