Finer Things in Mac

Your custom icons are represented well in the Documents side of the Dock, and even in Stacks.

An application’s minimized windows will hide in the Dock along with any others, disappearing from the right side of the Dock until the app gets reactivated.

While in Dock-Exposé, clicking on other Dock applications will show an Exposé view of that app’s windows, including any that are minimized (you can either click and hold on a Dock icon to enter this view, or press Tab while in Exposé All Windows mode to cycle through apps as well). Pressing Command+Tab will allow [...]

Hold the Shift key when launching Exposé, Spaces, Dashboard, minimizing a window into the Dock, or even when using a Dock Stack, and you will get a slow version of the feature’s animation.

Earlier versions of QuickTime played video in the icon in the dock.
QuickTime X doesn ot do this anymore; it just displays a static thumbnail when you minimize a video.

When you drag an e-mail address from any other application onto the Dock icon for Mail.app, it creates a new e-mail with that e-mail address in the body of the e-mail. In the three years I’ve been using Mac OS X, I’ve never once dragged an e-mail address onto Mail.app in order to send it [...]

Stacks has an experimental view that is more like a Finder windows’ List view.
In order to enable, open up terminal and type:
defaults write com.apple.dock use-new-list-stack -bool YES
Then:
killall Dock
Now right click on a stack and make sure it’s set to “View content as: List” and when you click on it you’ll see it expand like above.
via [...]

While changing app through keyboard (Command-Tab), pressing the down arrow launches Exposé on the selected app. Further, pressing Tab in Exposé’s All Windows mode will begin cycling through the windows of each individual application from left to right in the Dock.