Wikipedia
Splashtop (previously known as SplashTop) is a proprietary Linux distribution intended to serve as instant-on environment for personal computers. The original concept of Splashtop was that it was intended to be integrated on a read-only device and shipped with the hardware, rather than installed by the user. It did not prevent the installation of another operating system for dual booting. It was an instant-on commercial Linux distribution targeting PC motherboard vendors and other device manufacturers. The first OEM partner for the original Splashtop was ASUS, and their first joint product was called Express Gate. Later, other computer manufacturers also built Splashtop into certain models and re-branded it under different names. The aspects below detailing these events are retained verbatim from past articles, for historical reference.
It boots in about 5 seconds, thus is marketed as " instant-on." It uses Bootsplash, SquashFS, Blackbox, SCIM, and the Linux kernel 2.6.
Support for Splashtop OS has been withdrawn and downloads of Splashtop OS have been disabled on the Splashtop website.