Productivity is what's left over when you take your time spent at work and subtract getting morning coffee, checking email, deleting spam, surfing, blogging, noding, eating lunch, chatting with coworkers, perusing newsgroups, playing solitaire, alt-tabbing to and from solitaire, alphabetizing the books in your bookshelf, creating a radically new and different magic system for role-playing games, frantically jotting down ideas into Notepad for a living room MP3 player in the chassis of an old tabletop radio, considering strategies for your Civilization III game at home, deleting the new spam that just arrived, running to the washroom, grabbing a snack and a can of soda, shopping online for Christmas presents, instant messaging your significant other, looking for an MP3 of that one song that's been running through your head all day and won't go away until you've heard it, checking the weather, researching fascinating topics that are only marginally related to your work (if at all), rebooting your computer after it crashes right as you were engrossed in the Acts of Gord, creating a Javascript function to count down the number of days until your next vacation, worrying that you won't meet your deadline because you've been doing all this other stuff...

After all of that, hopefully it's somewhat higher than zero.

Maintains some semblance of an inverse relationship with procrastination.