SPARQL endpoints

Dear all,

Does anyone know about an official w3c SPARQL endpoint and validator?
I came across this list: http://esw.w3.org/topic/SparqlEndpoints and 
this one from the Spanish w3c website - http://www.w3c.es/Prensa/sparql/
But most of the endpoints in the first list seem to be down or not 
accepting specification of "FROM" in the queries.

Thanks
Lena