Today, the team behind the SURBL domain blaclists announced a new, experimental blacklist: xs.surbl.org.
As announced on the SURBL-Announce list: "An experimental source of some snowshoe and pill domains is now being published in xs.surbl.org. SURBL considers this feed to be experimental and would very much welcome feedback about it, particularly about any false positives. Does anyone know anyone who actually wants to receive snowshoe messages?"
You can read the entire announcement here.