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

Njam


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

Cyberduck


cyberduck.ch
Mac OSX
An easy to use FTP client for OSX. Even comes with a widget interface and example applescripts showing how to automate FTP transfers.

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.

GIMP


gimp.org
Mac OSX, Windows, Linux
The GNU Image Manipulation Program. Or as I like to think of it as the open source equivalent of Photoshop. It is a freely distributed piece of software for such tasks as photo retouching, image composition and image authoring. It works on many operating systems, in many languages.

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.

iStache!


freemacware.com/istache
Mac OSX

This programs sole purpose is to help putting staches on your photos. Nice!

Bonjour Browser


www.tildesoft.com
Mac OSX
The application will scan the LAN for any nodes which are Bonjour enabled, and present them in a single window.

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.

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).

Img2icns


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

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.

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.

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.

SpamPal


www.spampal.org
Windows
An in genius open source program which works to filter out spam email on your Windows computer.  The program works by actively monitoring traffic coming into the POP and IMAP ports, and therefore does not need to be setup for a specific email client (making the setup very simple and effective).

NmapFE


faktory.org/m/software/nmap/
Mac OSX
A popular port scanning and network security utility; NmapFE for OS X is a no hassles, GUI version for us Mac users.

Iceberg


s.sudre.free.fr
Mac OSX
A program which helps in the creation of OSX installer packages (.pkg files). Combined with Apple Remote Desktop, package files can be a powerful tool in the management of large scale Mac deployments.

MyHome


software.relevantwalk.com
Mac OSX
An excellent addition to any elementary school who uses locally managed accounts in OSX and has students manually mount their home folders.  Just put MyHome in the dock, and no more "I forgot how to get to my server."

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.

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.

MAMP and WAMP


www.wampserver.com
Mac OSX
The ultimate web programming and design test tube.  Both WAMP and MAMP are self-contained environments running Apache, MySql, and PHP.  Meaning you can develop "traditional" websites and/or complex CMS web portals from the comfort of your personal computer. No knowledge of setting up web servers is required. WAMP is for Windows, and MAMP for Mac folk.

Smell-O-Mints


www.jschilling.net
Mac OSX
The periodic table of elements never looked so good. With an aqua and brushed metal interface, this periodic table will display basic characteristics of each element when you click on them.

QuickSilver


blacktree.com
Mac OSX

Possibly my favorite utility ever created for OSX.  It is hard to describe what the program does exactly.  But I guess it could be called a application launcher.  Basically you press the specified shortcut key, and then start typing the title of what you want to launch be it a program, address book entry, bookmark, etc.  Sounds simple, but it can have a big impact on the way you navigate OSX.

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.

Disk Inventory X and WinDirStat


windirstat
Mac OSX, Windows
Both programs are similar in function.  DiskInventory X works in OSX, WinDirStat in Windows.  When opened both programs index the files and folders on your hard drive (this could take awhile), then display the sizes of said files and folders graphically.  This helps answer two important questions:
1.  "Who is taking up all the space on my file server" - Network Admin
2.  "How do I get rid of this message saying my startup disk is full" - User

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.

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