Computer Identifier and SMS in LAN

This code will list all the computers in the "LAN" network. (It takes a minute to list). To send short messages you have to select/multiselect the user and then send messages. I have used "net send" in WINNT. I got this code "network computer name identifier" here only. I have modified and added codes to use it for chat. This chat will work only on WIN NT machines. Comments awaited.