Here's a task for you, work out what your most played video game is and roughly how long you've spent on it. I think this could be interesting.
If The Orange Box counts as one game, then my most played is this.
Half Life 2: Finished it twice : About 15 hours per playthrough = 30 hours
Half Life 2: Episode One: Finished it two and a half times: About 5 hours per playthrough: 12 hours
Half Life 2: Episode Two: Finished it once: About 5 hours per playthrough: 5 hours
Portal: Finished it twice and gotten bronze/silver medals on most of the portal challenges: About 10 hours
Team Fortress 2: Adding together all the time the game says I've spent as each class: 82 hours 45 minutes.
Overall: 139 hours and 45 minutes. That's nearly six days, it's 8385 minutes and it's 503100 seconds.
If the orange box doesn't count as one game, then my most played game is still Team Fortress 2.
What about you guys?