Will just post those that immediately come to mind, but there is a lot more.
The Witcher 2:
Radovid: "Politics is like a complicated puzzle. Every piece might prove useful, or equally useless, even harmful."
CnC:
Kane: "Control the media, control the mind"
"One vision, one purpose. Peace through power!"
"It is the death of fear and the birth of hope. Rejoice children of Nod! The blood of your oppressors will flow and 50 years of tyranny will finally end. Transformation is coming, a new day will dawn. The future....is ours"
Everything else he says.
DA:O:
Loghain: "The emperor of Orlais also thought I could not bring him down. Expect no more mercy than I shwoed him. There is nothing I am not willing to do for my homeland!"
Alpha Protocol:
Mike Thorton: "I've travelled all over the world to stop you, you think I didn't make a network of my own? I have Surkov in Moscow. Shaheed and al-Samad, they may not like me but both are willing to do business with me. I've got one of the highest ranking officers in the Chinese secret police on my side. Steven Heck. G22. SIE. You hired Scarlet to kill Sung but now, she's with me. Then there is Parker, the guy can use his little talent to really stir things up. So I don't need you anymore, I can make my own Hallbech. Then I can make the world any way I want."
The last one is pure epicness of unmeasurable proportions.