Good news for all Mac CCleaner fans... you can now download and update CCleaner directly from the Apple App Store.
Click here to visit the CCleaner page in the App Store.
CCleaner for Mac supports OSX 10.5, 10.6 and 10.7, along with all current versions of Firefox, Chrome, Safari and Opera.
Alternatively you can download from www.piriform.com/mac/ccleaner