MAC OSX 10.7 10.6 10.5 -Hide the Dock and Menu bar on a per-app basis

To hack an app so that when it's active, the menu bar and dock are hidden, you need to find its info.plist file. Control-click on the program in question, choose Show Package Contents from the pop-up menu, and then navigate into the Contents folder.

Once there, add the following to the file:

<key>LSUIPresentationMode</key>
<integer>4</integer>

Be sure that it goes in alphabetical order, otherwise it won't work (i.e. LSUIPresentationMode goes after LSMinimumSystemVersion but before NSAppleScriptEnabled). Save the file and enjoy.