Hold item ideas?

I'd like to see everyone's ideas for new hold items. Here's mine!

The Power Bandana

Pros and Cons:
+Super Effective moves become neutral
-Reduces Defense and Special Defense
-Doesn't work if the holder has Wonder Guard

Magic Mushroom-

Pokemon holding the item turns into Mario for 2 turns.

Not sure if this is overpowered or not, but I always thought an item with a slightly weakened Technician ability would be really cool.

Squeeze Toy: A pokemon holding this item will have all moves with a base power of 40 or less have their power doubled.

I also want an item that would be like a reverse Soothe Bell, I'm so tired of Frustration being a useless attack.

Danger Ball: A pokemon holding this item will not gain Happiness and will lose Happiness with each step you take.

Moving this over to PGC since it has to do more with the games than the franchise in general. ^_^

Frozen Collar

+Turns Normal-type moves into Ice-type moves.
-Deals damage to the holder if it is not an Ice-type. (It would be bad news for some Dragon or Ground-types.)

Type Orb
+Powers up STAB moves
-User can only use STAB moves

I thought physical defense version of assault vest, but soon I found some reasons on the internet why it doesn't exist.