Just been reading over on engadgetmobile.com about a secret HTC device that's been uncovered. The North America only handset is labelled the HTC QUAR100.
The info has been dug up from the Bluetooth Special Interest Group's Web site.
My guess is it's probably name for the CDMA of the HTC Touch Diamond (Diamond..QUAR..Quartz?).

But could it also be Sprint's Android phone?
http://www.engadgetmobile.com/2008/0...can-exclusive/