• QuickSilver - QuickSilver is, by far, the most useful piece of software I have found. It lets you launch apps with ease, get names and e-mails from your address book, solve math equations... The list goes on.

• SideTrack (PowerPC Laptops only) - SideTrack lets you assign the sides of your touch pad to scroll around web pages and taps to the corners activate expose and right click. Unfortunately, this is the only non-free program on this list. Its just so useful thou, I couldn't help but put it in.

• VLC - VLC is, hands down, the best media player I have ever seen. It can play just about any type of video you can throw at it (any sort of AVI codec - divx, xvid, DVDs, VCDs, you name it) and most types of audio too.

• AdiumX - Adium is a neat little chat client that lets you talk to people using MSN Messenger, AIM, Yahoo! and many other networks. There are also lots of very well made skins and themes to download, so Adium will look exactly the way you want it to.

• DeLocalizer - If you're running low on space, or just don't plan on learning to speak each of the 40-odd languages OSX supports, DeLocalizer will scan your computer and remove all the language files that you do not plan on using. I find it usually frees up almost 1GB of space.

• Firefox - It's great on Windows, its great on Linux and Mac is no different.

• TinkerTool - TinkerTool lets you tinker with various parts of your system.

• NeoOffice - A native Mac OSX port of OpenOffice.org. Its not great, but it can do everything the Microsoft Office suite can do (and then some more - like a math equation editor).

• LyX - LyX is a graphical LaTeX editor. It also has a top-notch math editor (I can take math notes almost as fast as the prof can write them).

• All this said, I still use TextEdit for 90% of my writing.

• Gimp.app - An excellent port of The Gimp to OSX. For those of you who don't know, The Gimp is a photo manipulation program.

• Inkskape - An open-source SVG (Scalable Vector Graphics) program (similar to Adobe Illustrator). It is extremely powerful and the development team is always cranking out new features.

Some of the software listed here (Gimp and Inkskape, for instance) need Apple's X11.app. For OS 10.3 users, it can be downloaded from apple.com and 10.4 users can find it on their install CD (run the installer from the Utilities directory).

For the most part, things “just work” on Macs. For instance, you don't usually need to install drivers when you plug in a printer or a USB flash drive. Try the device first before installing the drivers it came with (they usually come with a bunch of crummy software you probably don't want).

Macs have these nifty “auto-sensing eithernet ports”. This means that you don't need a cross-over cable to connect two computers togeather. If you need to connect your computer to someone else's (for instance your laptop to your friend's desktop), it is as simple as plugging in an ethernet (CAT5) cable between them, then opening up the System Preferences, clicking “Sharing” and clicking the “Internet” tab at the top. From here, you chose “Share your connection from: AirPort” then check the box beside “Built in Ethernet” and click “Start” at the top. You may have to un-plug the ethernet cable and plug it back in, but the computer you are connected to will both be able to use your computer's Internet connection AND share files and the like. Just be sure to turn Internet sharing off when you are done (it can cause problems if you plug your computer in to a network afterwards).

TextEdit.app (in the /Applications directory) can read Microsoft Word files and save RTF (Rich Text Format) files. RTF files are similar to Microsoft Word files, except they are much more portable. Additionally, TextEdit can do most of the word processing you will ever need done (it can do formatting, fonts, spell check, etc) with none of the long load times of other editors.

Finally, spend some time playing around with your system. Don't be afraid to go in to the Applications directory and try programs out if you don't know what they are. Open up the System Preferences and see the neat stuff you can do.