who knows what this is?

i believe it's a recording studio owned by Stone and another guy.

Litho is a Latin/Greek prefix which means "stone"
Pretty clever.

It is a recording studio owned by Stone Gossard and it is located in Seattle.

I do know that Dave Matthews (who now has a residence in Seattle) recorded a substantial portion of his solo album "Some Devil" at Studio Litho.
Soundgarden recorded part of Down on the Upside there.
Parts or all of No Code, Yield, and Binaural were also recorded at Studio Litho. I believe that is the studio you see on Single Video Theory.

The current rates for studio time are $1,200 for a 12 hour day or $6000 per week. Stone has a nice little website for the studio. You can find it on the internets.

it was a secret code .. given to underground RM cd/dvd traders ...

here's more info on thy studio.

http://www.studiolitho.com/