rocketmail was one of the first major, free webmail services. the service was originally a product of four11 corporation. for a brief time, rocketmail battled with hotmail for the number-one spot among free webmail services. four11, including rocketmail, was acquired by yahoo! in 1997 for $92 million. yahoo! assimilated the rocketmail engine. yahoo! mail was essentially the old rocketmail webmail system.