Discovered within the contents of the Gigaleak, Sleep is a Super Nintendo prototype that makes use of the SNES Mouse. The ROM can be run after combining the two .BIN files. It is required to have an SNES Mouse set to the second controller port in order to get past the initial zone selection screen.
It is believed that Sleep could be the cancelled SNES game BLACK OUT, which was slated to be the second Nintendo game to utilize the SNES Mouse after Mario Paint, before development was stopped ahead of its slated November 1992 release. Dates of files and assets connected to Sleep match being made around the timeframe that BLACK OUT would have been in development, being the same time Mario Paint was developed as well.
Many have reasonably speculated that Sleep / BLACK OUT eventually became Mario & Wario, a game that used the SNES Mouse as well and features similar gameplay.