Might be nice until they get destroyed the first time they get left on all day. Also would be extremely time consuming to replace/repair with every occurrence. Maybe if a timer were built in it would be worth a try. Detroit lockers have been around for a long time.
My Tacoma has what Toyota call E-LSD. It uses the ABS system to apply the brake to the wheel that is slipping (in 4WD as well as 2WD).
Not the best system, but it seems to work pretty well.