neowin[.]net/news/steam-beta-feature-lets-you-get-game-files-from-other-pcs-over-lan/
If you've got a game on your PC, & want the same game on a 2nd PC / laptop, you can transfer the setup files from one PC to the other, installing the game without having to download it a 2nd time. That could be handy if you have download caps for example.