Support for "persistent memory, " which means that you won't lose all your data when your batterydies (a feature the Treo 650 and several other Palms already have).
And the Unger Report eight-point plan for cutting back on oil involves a bonus ninth point, just sit in your car and listen to NPR until your batterydies.
For example, you shut off the unit or the batterydies, and you have to start at the beginning or go through a medieval process of physically recording track numbers.