If I get in the mood to play one of any number of games, they will override almost anything new I could possibly have. This includes but is not limited to;
Deus Ex
X-Com
Civilization 4
Hearts of Iron 2
Europa Universalis 3
Fallout 1 and 2
Sid Meier's Alpha Centauri
Age of Empires
Space Empires V
Team Fortress 2
Final Fantasy X
Morrowind
Transport Tycoon
and more and more.
Edit: The Communist Manifesto wasn't a bad read for me, but I've never encountered so terribly written a thing as Das Kapital.