We use http://en.wikipedia.org/wiki/G... which is a clustered Postgres implementation. It has its problems (Postgres 8.2? seriously?) But it is very fast for ETL and batch queries on large data sets. We house 100+TB and get excellent performance. Its commercial and you pay by the TB.
Then there is also AWS Redshift. We have found it to be quicker at some things and possibly cheaper but immature in its feature set (no UDF, etc). The thinking here is that if you have a separate system for ETL, Redshift would make an excellent data warehouse/ data market SELECT server. Pay by usage/ hour.