Hidden inside OS X are a cadre of settings and options that, for one reason or another, Apple never included a checkbox or picker for. For instance, did you know that you can use a third animation when minimizing a window to the Dock? You can get at these hidden features through the command line, or via one on a number of OS X utilities that provide a friendlier front-end to these controls.
My app of choice to get at these features is Tinkertool. It’s a freebie download by Marcel Bresink that’s been around since the early days of OS X, and it lets you get at extra features for OS X and some of its bundled apps.
Here are a few features worth tweaking:
Restore pre-Lion key repeat settings: Prior to OS X Lion, holding down a key let you repeat that character (for example, if you held down the E key, you’d end up with “eeeeeeeeeee”). In Lion and later, holding down a key brings up a special character picker that let you select characters like è, ñ, and ø. To restoreeeeee (*ahem*) the old key-repeat feature, go to Tinkertool’s General tab and select “Support key repeat.”
Don’t sleep your MacBook when pressing the power key: On the General tab, uncheck “Press and release to switch to sleep mode.”
Make icons for hidden apps appear semi-transparent in the Dock: If you use the “Hide app” feature frequently, you might find it useful to have a visual cue that a particular app is hidden. From the Dock tab, check “Use transparent icons for hidden applications.”
But there are many, many more. Go get Tinkertool and see what it can do for you.