Since before OS X we've been using Stickies to hold small pieces of important information that we need at hand.
There is a really powerful small feature of the Stickies.app in OS X that let's any sticky note float over all other windows making it visible at all times. To make a sticky float above all windows select it and press: Apple-Alt-F (Command-Option-F)
You probably know that there is an application called Keychain Access on your Mac OSX system. But did you know that you can reveal all the passwords stored in it? Keychain Access stores all kinds of passwords, such as Wi-Fi networks, ftp access, websites, mail, etc.
I personally like to open a new folder for each project and within that another folder for every version of the project. This way I can easily follow the progression, do not overwrite old files accidentally and can dump old versions easily once the project is complete.
Have you ever wondered if a client received your important email already? Don't you wish you had a way to tell?
It can be done, although it's a bit more complicated than just clicking a switch. Visit Spypig and follow the instructions for a one off tracking image that will be used to check the delivery of your email.
You can arrange to a grid all your document icons in a Finder window by selecting the menu View / Arrange by.
But, what if you want the snap to grid option to be applied to a few items only. Simply press the Apple (Command) key while dragging the icons in position. The icon will snap to place with a smooth transition. You can even do this to several icons at once.
Use the Eye Dropper tool to sample any color on your screen by clicking and dragging from your document to anywhere on your screen, even outside of Photoshop.
“Imagination is more important than knowledge. For knowledge is limited to all we now know and understand, while imagination embraces the entire world, and all there ever will be to know and understand.” - Albert Einstein
I know this is a Mac focused site, but I couldn't pass up the chance to share this with everyone. It seems Microsoft is offering their top of the line collection -Office Ultimate- for the insanely cheap price of $59.95! Yes, $59.95!!!
The only catches (besides the fact it's only for Windows) are that you need to be a student and have an email address from your school ending in .edu.
*UPDATE* - I hear you guys! I wish Adobe included this feature in every program they make, but unfortunately, they don't; however, they DO include it in After Effects, Lightroom, Premiere Pro and Soundbooth (all CS3 versions). So, if you use any of these programs, make sure you take advantage of this great feature.