Okay, this section is a little thin right now, I'll add more as I come across them, if you have any tips that you think should be added, email them in to me.
In the mean time, this site has a pile of tips and tricks already collected! MacTips also has a variety of tips and tricks that include not only OSX but also other applications
Of course, if you check out Apple's own OS X site you will get a really good feel for the features built into your system.
What is with all the cats? Ever walk into a conversation about computers and somebody asks if you are running Leopard yet? Or mentions a cool feature that they just found in Leopard? Ever feel like you are speaking a different language? Here's the deal. . . Apple has various versions of it's OSX operating system. They each have their own codename. Here's a rundown of the versions and their codenames:
10.0 - Cheetah
10.1 - Puma
10.2 - Jaguar (the system for MLTI v. 1)
10.3 - Panther
10.4 - Tiger (the current system and the system shipping on MLTI v. 2.0)
10.5 - Leopard (Will be on the MLTI image for 2008-2009)
Okay, so after hearing about this, my superintendent started singing "Wondering where the Lions are" . . .
Right Click for Windows Users: Simply hold down the Control Key and click on an object, works pretty much like right-click.
The Dock: Key combinations to do a variety of things with your dock:
Apple-tab will flip between the most recently used applications. Continue holding down the Apple key and repeatedly hit the tab key to bounce between all open applications.
Apple-Q will quit the application that is selected using the combination above.
Option-click: toggle 'Hide Application / Hide Others'
Option-click on Desktop: Hide Application(s)
Apple+Option: Hide Others
Control-click: Show Context menu (same as right-click) Right-click (or Control-click) an icon then press Option to Force Quit
Apple-click an application icon to open enclosing folder and highlight the application.
The Trackpad: If you have the option to tap the trackpad turned on you may have noticed that your cursor goes all over the place when you are typing. Open the mouse system preference pane and check off the box marked "ignore trackpad when typing."
Screen Shots: You have 3 options built into the system.
Option 1: If you find an image on a web site just hold down your ctrl key and click on the picture, you will get a contextual menu, one of the options is "download image to disk." This will save the image to your desktop.
Option 2: Hitting Apple Shift 4 (Apple Shift 3 will give you a full screen shot) will give turn your cursor into a crosshair (this works in any program) and you can simply click and drag out a box that contains the part of the screen that you want. This also saves a file to your desktop.
Option 3: There is a program called Grab in the Utilities folder on your computer that will allow you to do screen shots of windows, selected areas, menus, etc.
Zoom: Want to zoom in or out on your screen? You need to set this one up ahead of time, Open the Universal Access preference in System Preferences and click on the Seeing tab. Make sure Zoom is turned on. You can also turn it on or off by using the option, apple and 8 keys. Now to zoom in simply hold down the option, apple and + keys, to zoom out hold down option, apple and- keys.
Create an Archive: Need to create a compressed folder of files to email to somebody? Simply control-click on the folder and select Create Archive from the pop up menu.
Key Caps: Remember this one from earlier Mac operating systems? It used to be under the Apple menu and was really useful when you had to find all those oddball characters. It seemed to have disappeared in OS X but they just moved it to the Utilities Folder. You can also activate it by going to the International preference in the System Preferences. Click on the Input Menu Tab and turn on Keyboard Viewer. Then you can activate it by clicking on the flag in your menu bar.