Gnome shell 3.0 using the UGR recipe for 0.1.1 \"Nebula\" with some additional packages, themes & extensions built using UCK on a fresh copy of Ubuntu 11.04.
At the time this was constructed Gnome shell, Gnome classic & Unity work.
Read the Installation Note & a link to the thread I frequent is in the torrent comment.
This is a 64-bit version, a 32-bit version will probably be released no later than 21 June 2011.