Profit sharing is another term for affiliate, associate, referral, or partner programs. Basically, a web site that sells goods online agrees to share their profits with other web sites that sends customers their way. When a visitor from one web site clicks on a link that takes them to the merchant site and then buys something, the merchant site pays a commission to the referring site.
*There are a variety of profit sharing plans online. Before signing up for one, make sure you understand when and how you'll get paid.