Tip: if going to
Borobudur, stay at the Manohara Hotel right at the base of the temple (or at Amanjiwo if you can swing it...), and take the Sunrise Tour package. You'll get to the temple a full hour before the gates open to the public and will get to experience dawn from up top -- quite a beautiful sight. (I'm still kicking myself from not bringing along a tripod for my camera.)