Internet Archive suggests the original discussion was a Usenet thread; here is the link to Google Groups' version of it:

https://groups.google.com/d/topic/geometry.research/7pyFhAAy...

> Lol check this out https://www.google.com/search?q=is+-1+prime

I saw that, looking for references... very amusing. Even funnier (to me):

https://www.google.com/search?q=is+1000000101110000000000000...