What's a good-sounding set of earbud-style stereo headphones that works with the Treo 700? Bonus points if the headphones also include a microphone. Triple word score if they're Bluetooth.

The phone came with a set, but they sound moderately crappy, and they fall out of my ears.

(Other than that, the 700 makes a pretty decent MP3 player. I set up Missing Sync to keep my card filled with an iTunes playlist of "3+ stars, by recently added". Battery usage seems reasonable, too.)

Update: Most people recommended the Etymotic ER-6 headphones, but I am sad to report that they have no bass whatsoever. They sound cleaner than the crappy headphones that came with the phone, and they don't fall out of my ears, but if I have to trade "stay in my ears" for "have any bass at all", I'll stick with the falling-out kind. Dammit. I guess I'll try the Shure i2c next.

Update 2: I got Shure i2c, and they're awesome! They block outside noise much better than the ER-6, and most importantly, actually have a low end. They also come with 3 sizes of tips in 3 styles, so they fit really well. (And they have a mic, and the right 2.5mm plug.)