The Samsung Q1 is the only UMPC available (so far) that allows rotating of the screen and there have been reports (Kevin has experienced it too) of the rotation occasionally having problems. A Q1 owner (Boris) has written a utility in .NET 2.0 that allows rotating the screen to all four possible orientations and Boris claims it alleviates the problem that requires reinstalling the video drivers. You can find the download and additional information here.
-jk

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