A number of promo codes are currently available to Amazon.com Visa card holders, valid until May 15, 2008:

• $20 off $200 on electronics, computers and cell phones: 2IK9E6R8
• 10% off $50 on music : CDJLXT8U (Limit $20 per customer)
• $5 off $50 on DVDs: DVD5BFHR

Only one offer of each type is allowed per household, and it does not appear to be targeted, meaning that any Amazon.com Visa can be used. (Via FW).