What you don't think my collection of Hydr. Manifolds or Electro Matrix will be worth a lot when China comes!?!?! lol
On the more serious side:
There are a lot of items in this game that you can keep in your inventory until you need the PEDs (they might be worth something some day).
I kept a lot of Robot loots and made a nice profit when Low-Loss cabels started to be usable, something that used to be TT I sold for 145% I think it was.....
On the other hand I have stuff in there that will probably never be worth more then TT (Paladin Masks anyone?) or Knight Shin Guards (F) maybe?