ATI (now AMD) offers a trade-up program for its range of graphic cards. Just send them your old graphics card and get a $50 credit. They even make it simple for you to first order your ATI card online and allowing you to send in your old graphics card later.
For example if you wish to order the Radeon X1650 Pro 512MB AGP for US$199, just purchase the card using the trade-up program. You will be charged the trade-up price plus the trade-in rebate. Once you send in your old card, you get the difference. Your total cost will be about US$149.99.
Great marketing idea? You bet! However if you are ok using another graphic card manufacturer such as Diamond, or VisionTek, you should be able to get a price even lower for a similar card using the same video chipset with no rebates involved.