Irongeek's GUI HP Printer Display Hack
Back in 1997 Silicosis of L0pht (firstname.lastname@example.org) wrote a bit of exploit code for *nix systems that allows you to set the text that displays on the little LCD panel of an HP printer. It accomplished this over the network by sending packets to the JetDirect box hooked to the printer (or built into it).
I decide to write a new version in VB that uses WMI to see what printers you already have set up and allows you to check off the printers you want to display your message on. It's usage is pretty self explanatory, just type in and IP of the JetDirect box or choose from the ones that the program finds on your computer then hit "Send Display". Be sure to only choose printers that are indeed network printers and not local ones.
I wrote it in my free time so I could use it at work to send warning messages to the printers I manage. It has some legitimate uses as well as fun ones. The original program by Silicosis can be found here.
If you have a problem with ActiveX controls merge this REG file into your system.