So far I have unlocked:

Masks - all the beauties , octacon's mask and both of Raiden's masks.

Stealth Suit (No Alerts) (octopus - rank)

AC Costume: 50 cqc and 50 knife kills (Assassin rank)

Highest rank so far is Wolf.

So what have you unlocked?

Well I managed to get two awards, one was for killing "untold" numbers of enemies and triggering many alerts, and something else for not dying much. I don't think they unlocked many things, though I do have 3 of the beauties and Otacon

I would love to get the Big Boss mask and the patriot gun, but that is way to hardcore (Big Boss Extreme). I have completed Big Boss (hard) but extreme is extreme make one noise and those PMC soldiers hunt you down :(

Stealth suit is for no alerts? Lol, I'm not sure if my friend got it then, he beat the game with 2 alerts.

How many emblems can you get through a playthrough,because I did a who bunch of tasks like 400 kills,100 flipthroughs of Playboy,10 combat highs and some other stuff,but I only got one emblem; for CQC,after my third playthrough.

I have about 10 or more emblems - I have played msg4 three times.

He may of brought it for 4 mil.  I was aiming for that but it takes too long :P  Just do it on easy :P  You have to beat the game with no alerts. I did that and the cqc/knife kills for the assasins costume.  It makes easy - more fun and it makes it harder in many ways.

Just unlocked the solar gun and bandana :D After four plays I still haven't gotten bored.

Did we really need a thread for this? Well, I guess it's not my problem.

Let's see... I've completed the game three times.

1. Solid Normal: I unlocked the suit... and two Beauty facecamos? Otacon facecamo here. Eagle rank here.
   
2. Liquid Easy: I unlocked the rest of the Beauty facecamos? Also, I got Bandana and Stealth for no kills and no alerts respectively. Oh, and Raiden A facecamo. Wolf rank this time - a little surprise actually.
   
3. Solid Normal: I got.... What did I get...? Oh, now I remember! The Solar Gun and Altair costume! Raven rank... Oh, and after completing the game I got Raiden B facecamo, and at some point Campbell facecamo.

I still want to get at least Drebin facecamo and Hound rank, maybe even Fox and after that maybe, just maybe, if I can get Hound and Fox easily, Foxhound and Big Boss too.