You've been programming too long when...
When you are counting objects, you go "0,1,2,3,4,5,6,7,8,9,A,B,C,D...".
When asked about a bus schedule, you wonder if it is 16 or 32 bits.
When your wife says "If you don't turn off that darn machine and come to bed, then I am going to divorce you!", and you chastise her for omitting the else clause.
When you are reading a book and look for the space bar to get to the next page.
When you look for your car keys using: "grep keys /dev/pockets"
When after fooling around all day with routers etc, you pick up the phone and start dialing an IP number.
When you get in the elevator and double-press the button for the floor you want.
When not only do you check your email more often than your paper mail, but you remember your {network address} faster than your postal one.
When you go to balance your checkbook and discover that you're doing the math in octal.
When you dream in 256 pallettes of 256 colors.