Quick, run Notepad. (You’ll find it under Start | Programs | Accessories — and if you run this program often, you might want to make a custom shortcut.)

Now press F5. Instantly Notepad pops in a timestamp, like this:

8:43 PM 3/22/2007

Pretty useful, right? If only more applications supported this shortcut. (We learned earlier that F5 has a very different function in Word and Excel.)