Ambassador - Referral Automation, Made Simple.
Launchrock - Setup a viral "Launching Soon" page in minutes to attract potential customers and promote your site's launch.
Referral Candy - Run a fully automated, customizable and easy to integrate referral program for ecommerce.
Viral Loops - Viral Loops is a viral and referral marketing platform to launch ranking competitions, sweepstakes, pre-launch and referral programs.
Friendbuy - Customer referral program software and email opt ins for ecommerce.
ReferralHero - Powerful referral marketing platform for honest marketers.