Virtual Light Lab. VLL has demo versions for both Mac and Windows machines.The demo version does not allow you to save your work from session to session, but setting it up is so quick and easy that you'll be working with the two lights and a sphere in no time.
Vectorworks is my personal choice for CAD software. Vectorworks is one of the few CAD companies to hire theatrical lighting designers to join their team of programmers. They offer a free version for students and teachers to install on their personal computers. Schools will have to purchase the software if they wish to install it in computer labs.
Lightwright. The demo version of Lightwright is exactly the same as the regular version except that it has a maximum capacity of seventy-five lights instead of the usual 30,000, it will hold only fifty entries in each text category instead of the usual 6,000, and users are not required to register the program with John McKernon Software. For readers of Dramatics, the demo version will likely suffice. For those with larger production needs, a student license is available that is valid for three years.
GrandMA 3D visualization software. Similar to WYSIWYG, this program shows you what your lights will look like on your virtual stage using your Windows computer. This software is specifically designed to be an emulator for the GrandMA lighting control board. The manufacturer supplies the software for free and hopes you'll like it so much that you will purchase their board.