Sharedance is a high-performance server that centralize ephemeral
KEY/DATA Pairs on remote hosts, without the overhead and the complexity
of an SQL database.
It was mainly designed to share caches and sessions between a pool of
web servers. Access to a sharedance server is trivial through a simple
PHP API and it is compatible with the expectations of PHP 4 and PHP 5
session handlers.
from William Yodlowsky with some tweaks by me
