Procrastinating

Learning why procrastination is actually good for you at Stanford's study website
"Spending time" with significant other. So that's what kids call it nowadays...
Drinking beers.
Editing this wiki
Mindless web surfing
Reading blogs, sending gifts etc. on XuQa
Looking up high school friends on Facebook
Watching Daily Show clips on comedycentral.com
Obsessively checking email (thereby slowing down everyone else's email)
Continuously refreshing the WSO homepage to see shared photos
Reading emails sent to the WARP listserver
Writing emails to the WARP listserver on important topics such as: "If Yoda, Gandalf, Superman, and Voldemort had a four-way death match onboard the spaceship Serenity, who would win?"
Reading WSO blogs
Snack Bar!
Writing WSO blogs
Talking on IM
Text messaging really, really long messages
Addicting Games
Strong Bad Email
Something Awful or Slashdot or Fark, the black holes of the internets
Googlism
Playing with Photoshop
Getting a livejournal
Checking your livejournal friends list
Editing your livejournal format
Making livejournal icons
Reading a magazine
Renting a movie from Sawyer and watching it on your computer (may I recommend Secret of the Sock Monkey?)
Downloading a movie, (series, season's worth of programming from the network, Red vs. Blue, etc.)
Cleaning your room
Complaining about life to your roommate, JA, or total strangers
Going to other people's rooms and distracting them
Getting into pointless arguments at Ephblog or WSO blogs.
Reading webcomics (PvP, Penny Arcade, Something Positive, and The Order of the Stick are all great for procrastinating; also, check out this List of Webcomics.)
Playing WoW or similarly addictive computer games
Learning a new programming language
Finding and downloading programs for your computer
Writing a script to control your favorite IM program from the command line
Posting to the CS dept. sign.
Ride the CS dept. scooters all the way from the physics building to the math library.
Lathering, rinsing and repeating...several times
Making a big pile of leaves and jumping in it
Completing little tasks for the Amazon Mechanical Turk, and getting paid $0.03 each.
Dancing around your room
Playing Snow Bocce
Using this Wiki to play "My Dad"
Contributing to something pointless
Reading aaaaalllll the way to the bottom of this list.