Gloves of Thievery 16
Hat of Disguise 8 - Disguise self can get you a lot more places you otherwise wouldn't, better and more enjoyably than anything else still on the list.
Helm of Brilliance 15
Helm of Comprehending Languages 14
Helm of Teleportation 11
Winged Boots 1 - The relative ease with which D&D PCs can fly has been a thorn in the side of DMs for too long