Just bought a ton of new Steam games? Maybe you're swapping to a new computer and (for whatever reason) need to re-download your collection? Valve just made it a lot easier to batch-install multiple games.
Spotted by Steam Database, a recent Steam update now lets you right-click and install multiple games at the same time instead of going through the install dialogue for each game individually. All you have to do is select the games you want to install in your library--Shift + mouse click or Control + mouse click depending on how much granularity you need--and then right-click one of the highlighted games and hit Install.
The familiar Steam game installation window will pop up, except instead of a single game it will show you all the ones you've selected and how much cumulative space they'll take up on your drive. If you have second thoughts (or selected a game by accident) you can toggle it right from that dialogue screen.
It's a small change, especially compared to the recent UI overhaul and the extraordinary pace at which Valve has put out Steam updates recently, but it's probably the feature I'll use the most. I've got about 700GB free on this hard drive--I might as well fill it up. (And eventually wind up using the newfangled ability to hide games from your Steam library, no doubt.)