Many Steam games have cloud-saving features these days, making this tool less of a necessity. Nonetheless, for games that lack cloud-saving, GameSave Manager is a must. Besides the obvious benefits, this tool allows you to save to personal cloud-based services, such as Google Drive and Dropbox. You can even set it to sync automatically. Be sure to save this link.
Skinning is an often overlooked aspect of Steam, and while it’s purely superfluous, it certainly adds a personal touch and can make the client look gorgeous. If you’re feeling creative, you can have a stab at creating your own skin with Steam Customizer. It’s very straight-forward to use, letting users create basic skins by choosing an image and color scheme, but it also allows for far more complex editing to truly change Steam into a work of art. It also has plenty of eye-popping skins on offer at the official site. Peel back the skin and look here to procure a copy of your own.
Perhaps the most controversial entry on this list. Idle Master is a small app that allows you to “farm” Steam’s droppable trading cards. It does so by running alongside Steam and making it think that you’re constantly in a game. It can “idle” several games at once, and intelligently prioritize games in several ways. For example, games with high-value cards, or those that have the most card drops available. It’s more efficient than waiting for drops manually, because it knows exactly how long to idle each game before moving on, and can be left running 24/7. While it sounds dodgy, it’s actually perfectly legal, and you don’t have to worry about Valve banning you or branding you a cheater. The program itself is safe, open source, and can be obtained here.