During the Nerds Rule T-Shirt Sale, select nerd t-shirts drop as low as $5.99 at Tanga. There are 4 shirts priced at $5.99, and another 11 at $7.99. Shipping adds $1.99 per shirt, and most shirts are the lowest prices we could find anywhere else, on anything similar. The pictured Quadrilateral Parallelogram T-Shirt, for example, is $5.99, the best we could find by at least $9. All shirts are printed on cotton. Sales tax is not charged in most states.