ItemPickupOnly picked up by Hoppers

[coolAlias]

Items such as power orbs can be picked up and stored using hoppers, allowing players to get them into their inventory.

Doesn't seem to be any hook or method called which allows the ItemStack / EntityItem to determine if it may be picked up or not, so this may be impossible (i.e. not worth it) to fix.

[Shahelion]

Maybe look at how Azanor handles Thaumcraft's Aspect Orbs. Those seem to act similar to experience orbs, in that they can't be picked up by hoppers and such.

[coolAlias]

Experience orbs aren't technically items, they are just regular entities. I could do that, but then wouldn't it be more difficult for map makers to give power orbs, small hearts, etc. to players?