Rogue Amoeba has released Airfoil 4.7.5, which restricts searches to your local network to prevent possible issues with Back to My Mac and iCloud. The update also fixes an issue with failing to open a DVD in Airfoil Video Player, prevents a crash if the Transmit button gets pressed exactly as an output disappears, and provides some small improvements for Retina displays (a full Retina display update is yet to come). ($25 new with a 20-percent discount for TidBITS members, free update, 10.6 MB, release notes)
Option-click to Hide Apps Quickly
This trick has been available in the Mac OS for years, but many people still don't know it. If you have too many windows cluttering up your screen, you can hide specific ones easily as you work. When you're in any application, hold down the Option key and click on another app's window, on the Dock, or in the Finder to switch to that other app and simultaneously hide all the windows in the previously current app.