I don't have a controller... YET. So here are some of my ideas. some are better than others.
Modern Warfare 2
1) Knife Canceling - http://www.se7ensins.com/forums/topic/163689-semi-useless-knife-canceling/
2) Use Rockets in AC130 - http://www.se7ensins.com/forums/topic/293072-ac130-glitch-unlimited-rpgs-other-launchers/
3) Drop one man army for another weapon - http://www.se7ensins.com/forums/topic/168520-drop-one-man-army-for-another-weapon/
4) Moon Walkin' - http://www.se7ensins.com/forums/topic/161134-mw2-moon-walkin/
5) Tactical Insertion Gun Glitch - http://www.se7ensins.com/forums/topic/171798-tactical-insertion-gun-glitch/
6) Bomb Plant Glitch - http://www.se7ensins.com/forums/topic/303892-bomb-plant-glitch/
7) Closer Zoom while Aiming - http://www.se7ensins.com/forums/topic/173861-closer-zoom-while-aiming/
8) Extreme Third Eye - http://www.se7ensins.com/forums/topic/255212-how-to-do-an-extreme-third-eye/
9) Riot Shield Instant Kill - http://www.se7ensins.com/forums/topic/175950-riot-shield-instant-kill-almost/
10)Appear dead - http://www.se7ensins.com/forums/topic/142761-how-to-appear-dead-when-your-really-just-laying-down/
Reach
11)Lower Weapon in REACH - http://www.se7ensins.com/forums/topic/301782-how-to-lower-weapon-in-reach/
Gears of War 2
12)Kung Fu Flip - http://www.se7ensins.com/forums/topic/59617-kung-fu-flip-tutorial/
Gears of War
13)Random Glitches - http://www.se7ensins.com/forums/topic/27900-gears-of-war-glitch-list/
Modern Warfare 2
1) Knife Canceling - http://www.se7ensins.com/forums/topic/163689-semi-useless-knife-canceling/
2) Use Rockets in AC130 - http://www.se7ensins.com/forums/topic/293072-ac130-glitch-unlimited-rpgs-other-launchers/
3) Drop one man army for another weapon - http://www.se7ensins.com/forums/topic/168520-drop-one-man-army-for-another-weapon/
4) Moon Walkin' - http://www.se7ensins.com/forums/topic/161134-mw2-moon-walkin/
5) Tactical Insertion Gun Glitch - http://www.se7ensins.com/forums/topic/171798-tactical-insertion-gun-glitch/
6) Bomb Plant Glitch - http://www.se7ensins.com/forums/topic/303892-bomb-plant-glitch/
7) Closer Zoom while Aiming - http://www.se7ensins.com/forums/topic/173861-closer-zoom-while-aiming/
8) Extreme Third Eye - http://www.se7ensins.com/forums/topic/255212-how-to-do-an-extreme-third-eye/
9) Riot Shield Instant Kill - http://www.se7ensins.com/forums/topic/175950-riot-shield-instant-kill-almost/
10)Appear dead - http://www.se7ensins.com/forums/topic/142761-how-to-appear-dead-when-your-really-just-laying-down/
Reach
11)Lower Weapon in REACH - http://www.se7ensins.com/forums/topic/301782-how-to-lower-weapon-in-reach/
Gears of War 2
12)Kung Fu Flip - http://www.se7ensins.com/forums/topic/59617-kung-fu-flip-tutorial/
Gears of War
13)Random Glitches - http://www.se7ensins.com/forums/topic/27900-gears-of-war-glitch-list/