i always watch the credits^^ i like them and most time they have goodmusic and many times after the credits it happens something like a short video.

btw i really don't remeber many of my achievements but i remember this one from hexic:

  to build this in hexic is not very easy^^ 

with my first account i was top 100 in the world in hexic this was very cool.

rockstar table tennis "the savant" achievement was cool as well.

Shadow complex proven grounds. 10G. Say what you want. But beating the practice modes with no youtube guide is ridiculous

Also getting every single achievement on Gears of war 2.

According to true achievements my most difficult achievement was completing harry potter and the deathly hallows part 2 on expext... anyone who has played HPATDHpart2 will get how ridiculous this is. Took about 30 mins.

Noone in the world has the seriously 3.0 achievement yet... good luck with that! lol

Actually I thought my living legends achievement had the highest ratio but it turns out the highest is this one.

Big 'Ol Pile of WinsWin 500 Online Ranked matches

171

(20)

8.57

11 Feb 11

I just looked at my top list and it is absolutely dominated by Rock Band and Guitar Hero games.

Halo 3 vidmaster-
beat the last level of Halo 3 on co-op legendary with Iron skull on and all 4 players in a ghost. Most fun I've ever had getting an achievement even though it was worth 0g

Halo 3:ODST vidmaster-
beat the level where you escort the engineer in the dumptruck without ever getting into a warthog on legendary with 4 player co-op and Iron skull on . There are two mongeese hidden in an underpass with rocket launchers that have 1000 ammo, which makes the achievement even possible to do. Even with that it was still ridiculously hard but also so much fun.

That's funny, I just registered on TA and that's what they say;

1 Perfection 319
2 Redeemed 222
3 King of the world! 210
4 Insanity 178

First one for Split/Second, first place in every race. Second is the 100% in RDR, 3rd is the complete all 3 star challenges in Brink(Shittest game ever), and fourth is ME2 on Insanity.

yo_john is right, you need to look at your ratio and not the TrueAchievement Score.
If the game is generous and gives you 500GS for a single achievement and everybody who started the game achieved it, you will get a TA score of 500.
Therefore to determine how difficult an achievement is you must look at the ratio which indicates how many people got this achievement compared to the ones who played the game but didn't get it.

My top 5 by ratio:

Race Driver: GRID - Gotta Drive 'Em All - 115 (30) 3.84
Tony Hawk's Project 8 - Sick Highscore Run - 76 (20) 3.82
Need for Speed: SHIFT - Epic Master - Earn 20 Epic Badges - 93 (25) 3.72
Tony Hawk's Project 8 - That combo was sick! - combo over 5,000,000 points - 128 (35) 3.65
Tony Hawk's Project 8 - Hit 50% of the gaps - 70 (20) 3.48

My top 5 by TA score:

Call of Duty 2 - War Hardened - Complete on Hardened or Veteran difficulty setting - 317 (200) 1.58
Need for Speed: SHIFT - NFS Live World Champion - 266 (150) 1.77
Tony Hawk's Project 8 - You made it to spot 4! - 250 (75) 3.33
MX vs ATV: Reflex - Greatest of All Time - Place 1st in all events in the MotoCareer - 249 (100) 2.49
Turning Point: Fall of Liberty - Presidential Medal of Freedom - Complete Insane difficulty - 248 (100) 2.48

EDIT:
a few notes:
- The RaceDriver GRID achievement is glitched. That's why it has a high ratio.
- I did the Epic Master achievement for SHIFT without any of the online badges.
- Call of Duty 2 - War Hardened is due to what I said at the beginning of this post highly inflated
- Turning Point is a bad FPS but there are still some (Duke Nuke Forever *cough* for example) which are way worse

Oh, the one i listed as my hardest at the start of this thread actually has the highest ratio too. 4.61!!!! 

MarathonThe player has completed the Ultimate Endurance tournament without any faults.

184

(40)

4.61

Beat that bitchez!!!!