Re: Multiple Budypress Networks, one install
I just replied to a topic about Virtual Multiblog. It treats each WP blog separately – including userbase, themes, plugins, login. So you could potentially have multiple, separate BP installs running on one set of WordPress files.
It does require a little knowledge of symlinks and vhosts, also not sure how things like the new multi-site functionality in WP 3.0 will work with Virtual Multiblog… but it’s an alternative!