I am now selling merchandise:
I tried selling t-shirts a long, long time ago... it never caught on. But I really like this design, so I'm going for it again: "Technology Is Not Your Friend" is now more than just a spiffy site motto, it's a wearable spiffy site motto. Wear it to work... especially if you work in IT.
I am currently selling this through Zazzle because I can't afford to buy my own stock and ship it myself. A basic t-shirt sold at my Zazzle storefront sells for $14.95, with discounts for bulk purchases. Zazzle lets you choose your own T-shirt style and color with a pretty nifty web app (written in Flash, I think). Different styles affect the sale price.
(Also, assuming you're interested, I don't advise getting a shirt in a color other than black or white -- the image doesn't seem to work well on gray, yellow, green, blue, etc.)