I've come up with a driver so that Elasticsearch can store its index data in Cassandra. I'm not sure how well it performs, as I haven't really put it through any big data sets. But you then get the advantage of data durability in Cassandra and the search capability of Elasticsearch.
It's very experimental, but I'm going to open source it sometime, I'd like to know if some people could really test it with some big data.
