Most rare games you own on your Steam account?

My games that have been removed from steam since getting them or at least this version:
A-Train 8
Actua Soccer 3
Air Control
Batman: Arkham City™
Chaos Ride
Clive Barker's Jericho
Cryostasis
Deus Ex: Human Revolution
Deus Ex: Human Revolution - The Missing Link
DiRT 2
DiRT 3
Divinity II - The Dragon Knight Saga
Droplitz
Gotham City Impostors
Grand Theft Auto
Grand Theft Auto 2
Mafia
Neverwinter Nights 2: Platinum
No Time to Explain
STORM: Frontline Nation
Scratches: Director's Cut
Section 8
Shattered Horizon
Space Rangers
SpaceForce: Rogue Universe
Star Wars Galaxies
Starvoid
The Chronicles of Riddick: Assault on Dark Athena
The Ingenious Machine: New and Improved Edition
The Whispered World
Thunder Wolves
UFO: Afterlight - Old Version
World War 1 Centennial Edition
Your Doodles Are Bugged!
Zombie Driver

The Original Strife: Veteran Edition

Insta buy once i saw it on steam.
Nobody in this thread seems to have mentioned it ;D

Cryostasis
Deus Ex: Human Revolution
Deus Ex: Human Revolution - The Missing Link
GEARCRACK Arena
Ion Assault
Rhythm Zone
Scratches: Director's Cut
The Whispered World
Transcripted
Wallace & Gromit Ep 1: Fright of the Bumblebees
Wallace & Gromit Ep 2: The Last Resort
Wallace & Gromit Ep 3: Muzzled!
Wallace & Gromit Ep 4: The Bogey Man

I still can't get over the whole thing with Transcripted. It sucks. :\

Batman: Arkham Knight

Pong

Deadpool is probably all I have that's rare. I have lots of games that were removed from steam but they are still available on other sites and pretty affordable. Some people are selling Deadpool but it's over $100 bucks now so that's why it's rare.

Valkyria Chronicles

Towerfall Ascension + Darkworld Expansion. I wouldn't say this game is rare. But none of my friends have them.

I have gift copies of family guy and the dlc that aren't on steam anymore

Blur
So fun

Deus Ex: Human Revolution i guess... it was removed

Afterfall insanity

Is Paranautical Activity still not available? If so that's probably the rarest one I own.

Don't feel like going through my entire library, but looking only at the games I've installed, none of my friends have played:

• Blackguards 2
• Dead State
• Jagged Alliance Flashback
• Maia
• Satellite Reign
• StarCrawlers

Lords of Xulima
Alice: Madness Returns
Continue?987654321
Marlow Briggs
OMSI 2

Cart life

Naruto shipuuden ultimate full storm 3 or something. Probably not a rare game itself, just that none of my friends have it.
Rome 2
praetorians.
Inversion. Havent even played it, but i have it lol.

And what is the easy way of determining which of my hundreds of Steam games is played by which of my hundreds of friends?