GOG provides downloadable installers so that I can back-up my games. This means that I get to keep my games no matter what happens, as I can re-install them from my back-ups and don't even need an Internet connection to install and run the games. They also have excellent search features on their site, so games are really easy to find. Almost every title is DRM free and the catalogue includes a lot of classic games that are now hard to find, often with amazing deals.
