Your guess is as good as mine, but not as good as ours.
Have you read The Wisdom of Crowds by James Surowiecki? I haven't either, but I know enough about it to inspire this little experiment:
One of Surowiecki's examples is the old "how many jellybeans?" guessing game. He claims that the average of all the guesses will probably be closer than any of the individual guesses.
Unfortunately I'm fresh out of jellybeans, but as you know the Black Hole Friday sale is this weekend, so I thought we'd use that for some data.
Here's the question: What do you think the maximum number of visitors at one time on Threadless.com will be over the weekend?
Cast your guess in a comment below. I'll find a prize for the person who comes closest, and a bigger prize if someone nails it. All entries must be in by 12:01am Friday.