From Auratech Software:
Auratech Affiliate Link Cloaker helps you hide your affiliate program links from your visitors. If it's too obvious that your link is an affiliate link, people might not click on it or they might go straight to the main URL of the link. They may also substitute your link with their own affiliate ID. This means you will not receive a commission from these users even though you were the one who referred them. To solve this problem you can cloak your link. Our software makes it quick and easy to protect your hard earned commissions.