These may already be on the list but....
The nurse checks your pulse at the doctors office and immediately begins CPR.
You can't sleep without a bottle of water by your bed.
If you only drank 8 glasses of water a day you would die.
You can check your pulse in bed at night just by listening to it.
You put in a couple of 60 mile weeks because you want to take it easy.
You say things like, "I only ran 10 today", or "I only ran once today."
You think soccer players are out of shape.
You say things like "long and hard" to your female friends and it is not a sexual inuendo.
You have heart rate competitions with your running buddies.
You think anyone slower than you is not a runner and anyone faster is just a freak.
You find track on television exciting.
You can get drunk at the bar for $2.50.
It is no longer possible to sprain your ankles.
The girls on your track team think the Hooters girls are overdressed.
You can't understand why people would golf on such a beautiful XC course.
You spend more time on letsrun than surfing porn.
48 degrees is the perfect temperature.
You have no problem peeing in public.
You think Once A Runner is the best novel ever. Well it is.
You can't imagine not running.
You set your alarm for 6 am on the weekend.
You hate runners world.
You'll run 18 miles on a Saturday but must find the perfect spot at the grocery store because you hate to walk.
You don't Gallowalk.