Handspring has kicked off a trade-up promotion for its Treo handheld communicator that offers current PDA owners a US$100 rebate when they purchase a Treo 180. Customers need only to furnish the serial number from their previous handheld to take advantage of the offer, regardless whether unit is functioning or not. The offer is eligible to handhelds that use the Palm OS, Win CE, Pocket PC or Symbian operating systems, as well as Apple Newton, RIM Blackberry, Casio, Psion, and Sharp handhelds.