I spend a fair bit of time in Terminal, and I occasionally want to see what’s behind the Terminal window. There are many ways to do this, of course. I can move it out of the way, use Exposé, minimize it, or resize it. I could also use Terminal’s preferences to make the window itself permanently translucent, letting me always see what’s behind the window.
All of these methods work, but now, thanks to an anonymous Mac OS X Hints tipster, I’ve got another very easy-to-use solution in my tool kit. The following works if you’re running OS X 10.5 or newer, you’ve got Terminal’s tab bar visible (View -> Show Tab Bar), and you’re only using one tab. That may sound like a lot of limitations, but I’m almost always only working in one tab in Terminal, so this hint works well for me.
To see what’s behind your single-tab Terminal window, just click-and-hold on the tab and then pull it straight down. This is the motion you’d use to split one tab off into its own window in a multi-tabbed Terminal window. But when you have just one tab and pull downwards, something interesting happens–the window turns nearly transparent, and will remain so for as long as you hold the mouse button down.
Once you’re done viewing whatever it is you wanted to see, just release the mouse button to return your Terminal window to its normal state. I find this method, once you get used to it, to be a very fast and easy way to glance at something behind the Terminal window.