Looking for hosted Solr solutions I found also:

http://www.opensolr.com/

http://www.solrhq.com/

http://www.midwesternmac.com/services/hosted-solr-search

http://www.netaphorsearch.com/products/solr-hosting

http://www.acquia.com/products-services/acquia-network/cloud...

(they're mainly targeted to drupal)

anything else?