Jeffrey Richter has created a utility called PushPin which he has been adding features to for many years. Using hotkeys, PushPin allows you to pin any window on top of other windows, change the opacity of windows, rotate the display, show a countdown timer, touch file timestamps, download files from the web, determine which app(s) have a file in use, navigate to registry keys in RegEdit.exe, dial phone numbers via Vonage or Google Talk, and more.