Mobile social-networking software developer IceBreaker Inc. announced Tuesday that its Crush or Flush messaging utility has passed trials and is now available for use with the Boost Mobile telephone network. Crush or Flush, IceBreaker explained, is a casual messaging service that enables its users to chat anonymously, maintain and browse personalized profiles, and manage customized "Crush Lists" featuring fellow users who expressed an interest in getting to know them. Based in Irvine, Calif., Boost Mobile’s network boasts some 4.5 million subscribers. According to IceBreaker, Crush or Flush launched in January and now has more than 250,000 members. IceBreaker is headquartered in Bellevue, Wash.