Developers of the Spring RTS engine, a GPL game project. Spring is an RTS platform originally created to recreate the Cave Dog classic, Total Annihilation, in full 3D, but has since adapted into a full scale engine capable of running virtually any type of RTS title, although favoring those using damage simulation systems still. Also directly and indirectly responsible for assorted apps to help with the development of spring games and allowing users to download spring related content and join spring related games.
Currently used by most projects. Note the spring sunrise which is the key branding element along with the "Spring" name