I ran across this discount code on another forum and thought I'd post it here. Hope it helps someone:

You give this discount code: 24456775153 to friends, neighbors,
relatives, the guy at the corner garage--anyone you know who works on cars
or trucks.
- When someone (including yourself) places an order at www.rockauto.com
and enters your discount code, he or she will receive an immediate 5%
discount on that order.
* If you are using our Java Catalog, enter your discount code in the
"How did you hear about us" line of the shopping cart
* If you are using our non-Java Catalog, enter your the discount code
in the "Discount Code" field of the Shopping Cart and click "Calculate
Discount"
- The discount code expires on August 16, 2005; so don't wait!