Below you will find links to down load some cool PC software... I'm not sure about Mac versions.

Multimedia
VLC         - A media player that plays more formats than Windows Media Player
Audacity   - A sound recording program

Engineering & Design
West Point Bridge Designer - Design & test bridges for efficiency ($)
Lego Digital Designer          - Plan out an NXT robot before your students actually build the robot

Graphics
Google Sketch Up               - A 3D drawing program
Google Earth                       - A program that let's you virtually fly to almost anywhere on the globe
Paint.net                             - A good paint program
Pixlr                                   - A good web based paint program
Pivot Stick Figure Animator  - A neat little program to make animations like the old flip card days

Antivirus
AVG                                 - I installed the free version after I got tired of Norton slowing my machine down
Spybot Search & Destroy   - I run this from time to time
Malware Bytes                   - I run this from time to time
Windows Defender             - I have not tried this one yet

Please contact Everett if you find errors or have information to post.