Its possible to root hack the Nook now and run Android 2.2 (and maybe
3.0) on it and should be able to install the current XCSoar Android
software and see if it works. I believe there is supposed to be an
official upgrade to Android 2.2 coming for the Nook which should make
this easier. Anybody tried XCSoar on the Nook?

Perhaps a foolish question, but since the Nook Color doesn't have a
GPS, how are you thinking of getting the GPS signal? I found that
there's an app called tetherGPS, but that uses an Android smartphone
to transmit over wi-fi to the Nook. Is there a way to feed the GPS
directly into the nook from another GPS source? Could it, somehow, be
connected to a PowerFLARM?