LaunchBox - LaunchBox is a portable, box-art-based games database and launcher for DOSBox, emulators, arcade cabinets, and PC Games. Download it free!
Ubisoft Club - Ubisoft Club app enables you to get updates about your favorite games timely.
Playnite - Source code generated using layoutit.com
itch.io - An online game marketplace and community.
GameRoom - Make your video-games library shine!
GOG.com - DRM-free game store, selling both new and old titles. No clients required.