Peng is a treasure found in the Hangar in between the two sidewalks. As you 
leave the Kellion for the first time, look over the railing to your LEFT. 
There is a small statue lying on the ground. You need KINESIS to get it, so
you can't grab it until Chapter 11. IMPOSSIBLE MODE Beat the game on any 
difficulty, save your game, and start a new game. Choose IMPOSSIBLE MODE,
then play until you save your game at a kiosk (in a new slot if you like).
The important thing to note is that impossible mode will not remain unlocked 
if you do not save a game that is playing in impossible mode. 

Unlockable        How to Unlock
-------------------------------------------------------
10 power nodes  - Beat the game on any difficulty level
50,000 credits  - Beat the game on any difficulty level
Backstory logs  - Beat the game on any difficulty level
Military suit   - Beat the game on any difficulty level