I'm still searching for an eventual replacement for my trusty i500 and I came upon this Motorola MPX 300 for sale on ebay:
eBay: Motorola MPX 300 (Brand New In English) + Extras (item 230138581721 end time Jun-08-07 10:10:54 PDT)

I did a quick google of it and found this: Motorola MPx / MPx300 review, price, specification - Malaysia cellular phone
among others. One site said it seems a little short on memory, but the 2 way flip is kinda cool. It appears it was canceled before mass distribution -- sound familiar? Looks like it might be a GSM/Pocket PC "evil twin"/"mirror universe" version of the i550 -- or at least in a similar "rarity" category since it's already at $285 with 2 days left.

Anyone know anything about this phone? There's not much info in the "Motorola MPx (300, not 200/220)" pdaphonehome forum, but it does have more activity than the i550 forum...