plan 9 foundation site is a good one,
I use it to reference plan 9 articles.
In fact I recommend you reading those articles too,
they're very interesting
By the way,
plan 9 as a unix rewrite is a rather clean system.
After using it for some time I understood
that gui and mouse are absolutely not that bad.
Actually,
I switched
to acme
from vi,
and I feel rather good there.
In general,
looking at another viewpoint is an interesting
and I'd even say healthy thing