NetPopUp 1.1

As of SP2 in Windows XP, Microsoft has desabled the service that allows you to send popups to other PCs. This was in response to unscrupulous advertisers using the service to pop up ads. This tool will still work if you specifically enable the service, but in my experience the only PCs that still allow this are old Win98 and Win2000 machines.

NetPopUp is a replacement for the Command Prompt tool NET SEND. This program allows you to send pop-up messages to other computers on your local network, or any PC that you have the TCP/IP address for. NetPopUp offers a few amusing benefits over NET SEND, however:

You can specify what you want to appear in the FROM line!
NET SEND always identifies your computer name when you send someone a pop-up. NetPopUp can make it appear those popups come from someone else! (For real amusement, try sending a message from "FCC" saying "You are playing an illegally copied MP3, a warrant has already been issued against you, and your equipment will be confiscated within 24 hours. Click OK to admit guilt.")
NET SEND cannot tell you which computer on your network are suitable to receive popups (OK, we wont call them victims, well call them recipients of inter-office-humor!). NetPopUp can! It has a network scanning tool that scans each computer on your network and reports all WindowsNT, 2000, and XP based machines that can receive popups.
NetPopUp is a nice simple Windows program. No command prompt needed!