10. You start writing PWADs and graphics patches.
9. Every time you see a bowling ball, you think: "Cacodemon"
8. You refer to Chewbacca as an "Imp"
7. You suddenly start spinning around without reason, and can only stop when you try walking in the direction you are turning...
6. You adopt the same stance while walking as a former human (upper torso thrust forward.)
5. Doom and related files takes up more space on your hard drive than Windows.
4. You start playing a mediocre game of Doom at 3pm and finish at 5am.
3. You get 150/150 on the Doom purity test.
2. You have at least one Doom sound effect on your answerphone...
1. You find excuses to write Doom top ten lists when you should
be doing work.