Freeware... because the software police will eventually carry mace.

TrueCrypt


www.truecrypt.org
Mac OSX, Windows, Linux
Creates encrypted virtual disk files for storing data which must be kept secure even in the event that your computer is stolen. The program can also completely encrypt an entire disk, such as a USB key chain.

Image Tricks


www.belightsoft.com
Mac OSX
This is not so much a image editing program as it is a image manipulation program. With Image Tricks you can apply a large number of effects to pictures using the core image filters built into OS 10.4.

SMARTReporter


corecode.at/smartreporter/
Mac OSX
Monitor your OS X (or OS X Server) hard drive/s. SMARTReporter runs in the background and periodically checks the SMART status of your hard drives.  SMART is a technology installed in the firmware of hard drives which detects hardware failures, or impending failures.  SMARTReporter can be set to popup alerts or send an email if there is a problem.

SeaShore


seashore.sourceforge.net
Mac OSX
Seashore is an OSX native image editor based on the popular unix program GIMP.  The program has the look and feel of Photoshop Elements,  and shares many of photoshop's features such as: layering, alpha masks, and channels.  Files can be saved as TIFF or JPEG.  Great for middle school classes that want to do more advanced image editing.

Gawker


gawker.sourceforge.net
Mac OSX
Makes time-lapse photography/movie making extremely easy using the built-in iSight on the new macs, or any attached camera. Just input the interval between frames, and what movie output you would like. Interesting also is it's ability to attach to remote cameras attached to other macs through bonjour.

Tux Paint


www.tuxpaint.org
Mac OSX, Windows, Linux
A kind of open source version of KidPix.  TuxPaint is a drawing program for children, and as such has big easy to use controls, lots of color, and lots of sound effects.  The developer's site has some great videos of the software in action. While your there remember to download the additional rubber stamps for the program.

Onyx


http://www.titanium.free.fr
Mac OSX
There are many system utilities people have written to access the hidden command-line options in OSX.  Onyx is my favorite of the bunch.  It allows you to do such things as show hidden files/folders, deactivate dashboard, alter the login window, increase the speed of Safari, clean every cache, run maintenance scripts, etc.

JumpCut and Clipboard Buddy


Clipboardbuddy
Mac OSX, Windows
Both programs are what is commonly called clipboard-buffers. This means they will quietly sit in the background on your computer and store things that you cut or copy to the clipboard. After using one for a bit you will find yourself wondering how you ever got by with only copy/pasting one bit of text at a time. JumpCut is for OSX and Clipboard Buddy is for Windows.

OpenOffice


openoffice.org
Mac OSX, Windows, Linux
The open source alternative to Microsoft's Office suite of programs.  I have been using the software for a couple years, and have been amazed how quickly it has matured. Open Office can read/write the common Microsoft formats (.doc, .ppt, .xls), and has the useful ability to save slide shows as flash movies.  Unfortunately it is not an OSX native program and must be run inside the the X11 window system.  I recommend NeoOffice for the OSX folks.

Picasa


picasa.google.com
Windows
An excellent piece of software made by the folks at Google to organize, edit, and share your digital photos. Very much the equivalent to iphoto for those poor people not fortunate enough to have a Mac.

ClamXav


clamxav.com
Mac OSX
Free virus scanning for OSX.  Yes it's true that viruses, for the most part, do not effect OSX users.  However, since most of the world uses Windows it is a good idea to make sure you are not emailing something harmful to your fiends and colleagues.  It also will scan for macro viruses which are a problem if running Microsoft Office on a Mac.

PDFCreator


pdfcreator
Windows

Every Mac user knows that you can create a PDF directly from any print job in OSX.  But did you know you can get the same functionality in Windows?  Enter PDF Creator.  A free tool which will act as a virtual printer, and create PDF files from any print job.

Integrity and Xenu's Link Sleuth


Integrity
Mac OSX, Windows
If you run a website, it is always a good idea to check peridically for broken links. These two programs are the best automated link checkers I have found. Integrity for Macs, and Xenu's for PCs.

Wink


www.debugmode.com
Windows, Linux
One piece of freeware I really wish they made for Mac. Wink is a Tutorial and Presentation creation software, primarily aimed at creating tutorials on how to use software (like a tutor for MS-Word/Excel etc).  Since you can save in flash format Wink makes it extremely simple to publish your tutorials to the web.

Img2icns


www.img2icnsapp.com
Mac OSX
 Img2icns is a converter tool for your images. Enjoy creating thousand of icons from your pictures.

Njam


njam.sourceforge.net
Mac OSX, Windows, Linux
Njam is a full-featured cross-platform pac-man-like game

iRedLight


www.filewell.com
Mac OSX
Greatly extends the use for that tiny Apple remote that came with newer Macs. It allows the remote to control many system actions and programs including PowerPoint, NeoOffice, and QuickTime. Comes in very handy for presentations in and out of the classroom. The remote buttons can also be mapped to applescripts (the possibilities are endless).

MacTracker


mactracker.ca
Mac OSX, Windows
A helpful program for people in charge of maintaining or repairing Apple products.  It is basically a database of all the specifications for every Apple product ever made. Constantly updated with new products by the developer.

Audacity


audacity.sourceforge.net
Mac OSX, Windows, Linux
A very nice interface for editing sound files, or recording voice.  It is a great choice for teachers interested in doing a podcasting project.

PHPList


www.phplist.com
Web-Based
An open source news letter manager which is easily integrated into an existing school/district website. It features RSS aggregation, scheduling, mailing-list opt in, tracking, and a bunch of other useful functions.

Camino


caminobrowser.org
Mac OSX
Camino is an OSX only web browser which combines the look of OSX with the Gecko rendering engine (used by Firefox). Definitely worth a look.

SpiceWorks


www.spiceworks.com
Windows
Is a network monitoring and inventory type software.  It can track and give all kinds of details about nodes on your network (PCs, Switches, Routers, Printers, etc). Unfortunately it must be run from Windows. But it can report on OSX, Linux, and Unix stations just fine.

AVG Free Edition


free.avg.com
Windows, Linux
Have Windows?  You need to worry about all kinds of security problems.  AVG will do a decent job of keeping your computer virus free... for free!
Please note that the free addition is only licensed for home/personal use.

Mouse Locator


www.2point5fish.com
Mac OSX
Great for presentations or demonstrations on the computer. Mouse Locator will put an target graphic around your mouse cursor whenever a set hotkey is used. You can set the duration, intensity, and hotkey combination.  In addition, Mouse Locator allows you to chose which graphic is used and weather or not mouse clicks should be highlighted.

Transmission


www.transmissionbt.com
Mac OSX
My favorite Bittorrent Client. Extremly Lightweight with just the right amount of features.

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