Metal Gear Solid 3: Subsistence Updated For The Better
First of all you get a lovely online mode which is brilliant especially when you kill you mates.
Secondly you get a duel mode where you fight all the bosses form Snake Eater and may get the extra camo thats avaliable.
There is a stupid Snake vs. Monkey mode where you have to round up some monkeys as quick as you can. This also earns you extra camo.
Lastly you get the original 2 metal gera games (the 2d ones). These are pretty good actually.
All in all if you already own Snake Eater no need getting this but if you don't it'll keep you going for a while.