Valve recently released a beta update for its Steam client that allows users to remotely install games to their local machine using the steampowered.com website.
After installing the beta update to the local Steam client (Steam > Settings > Beta Participation), just leave the client logged in on your machine. Then navigate to Community page of the Steam website. After that, click on the Games category where the website will then list all the games tied to your Steam account. If you have a game you want to download and install while you are away, just hit the install button to the right of the game’s name.
This is certainly an interesting feature for some, especially if you happen to be on vacation during a Steam Holiday Sale! (hehe). More details on the process can be found here. Is this a feature you’ll be using?