A lot of Mac users don't want to pull up Terminal and type arcane text into the command line, so MacDentro has a GUI front end that you can use to run those commands and keep your Mac cruisin'. IceClean, now at version 3.0.6 has menus for OS X Maintenance, Cleanup, Security and Network, and Utilities, all of which are packed with menu choices or keyboard shortcut equivalents that make mundane maintenance chores simple to perform.
There are other apps available -- Maintenance and MacJanitor come to mind -- that perform similar tasks, but neither of those programs comes close to the depth of capability of IceClean.
The price is right, too - it's free, although you might want to send the MacDentro folks a donation if you find yourself using IceClean regularly. Download IceClean here.
Tip of the hat to our very own Victor Agreda for this find!