I hope Big-Z doesn't mind if I butt in here but this is what I use and I think he's refering to the same thing.
Prismacolor Pencils
I'm not totally sure which type mine are- the Softcore I think though. I picked mine up at Michael's - I'm sure most art stores should stock them. I've used them for small areas like paint chipped off a prop but never to the extent that Carlos has here. I like them, they are very easy to control since it's well just like using a pencil.