Databases designed to handle large volumes

With the growth of the Internet, and most successful web projects, it is increasingly necessary to use scalable databases capable of managing efficiently large volumes of information.

Often traditional databases do not meet the requirements of these systems, or at least not with a reasonable cost, and so open source projects come into play with databases specifically designed to fill this gap.

One case that we have mentioned is that of Cassandra DB, a distributed database open source that already use Digg, Facebook and Twitter.

Today I've discovered another promising project. This is Hypertable, another Open Source distributed data storage system that announces maximum performance and scalability to handle large amounts of data. Has commercial support at www.hypertable.com and search engines such as Baidu, Rediff.com or Zvents are already using it.

It seems that the design of these systems is based on the project Bigtable, which Google created to manage the large amount of data to move applications and projects that are created. Enclosed is a pdf that provides Google with information about this project.

Has anyone tried Hypertable, or know any case of use of this storage system? Have you heard about or worked with other similar databases or systems?