What is your favorite item pickup sound?

So what is everyones favorite pickup sound in the game?

I have always been partial to the twist sound from picking up a box of shells, I also like the metal scrape sound from picking up smg clips, and the click sound from picking up cells.

Picking up the shotgun. I like it.

Security armor. Feels like cold steam coming out through a hollow pipe.

Picking up ammo in general.

Picking up cells, heavy chaingun belts or BFG cubes so I don't have to use the assault rifle.

 Soulsphere, plasma rifle, rocket launcher metal clang, armor, soul cube.