The TSUKI (月) Project was a website based on the belief that our reality is just one system among many in existence, and that when we die, we ascend to the next system.
Several references to the anime TV series Serial Experiments Lain were present on the website and its multi-reality theories.
In January 2017 a 4chan user, named Tsuki, got attention by launching the TSUKI Project.
The TSUKI Project alleged that by joining the website, the users called migrants, would transfer from Life (our present system) to LFE, the next system once they died, but warned users to not commit suicide.
The website gained interest from the internet community after being featured in numerous YouTube videos. Several theories were born from it as some said it was a hoax, others a death cult or even a marketing stunt for the release of a new game/TV series. Most information on the website was purposely cryptic with links leading to images of static and black and white pixels, leading even more theories about encrypted messages hidden on the website.
In 2018 the website came under fire due to the suicide of a seventeen year old boy directly influenced by the TSUKI Project. The TSUKI Project website has since been taken down and the last few users migrated to INITIATE or left completely.
Much of the website was later debunked, and/or explained by Apollobase.
Serial Experiments Lain
Many theories from users about the TSUKI Project made link with the anime TV series Serial Experiments Lain. In fact, the website itself made it clear by having the protagonist on its banner. Many users believed that the Tsuki project was based off the anime, however it turned out it was based on a visual novel.
Lain herself became the mascot of the website and gained great affections from the users. As the website worked as a forum around the TSUKI Project, it was a prevalent place for sharing Serial Experiments Lain pictures. While some subscribers used the website as a fansite for the TV series without believing in Systemspace, most did believe, as revealed by a survey of over 1,000 users.
The Cult of Systemspace (youtube; by Initiate)
TSUKI Project website (archived)
TSUKI Project website (mirror)
The TSUKI Project explained (reddit)