The Xen Ruby Library by Geoff Garside providers an XMLRPC client library for users of the Xen API working with XenServers. The Xen API, or XAPI, gives developers tools and an interface for the remote management of virtualized guests running on a Xen-enabled host.
Yahoo has just released a major update to YQL, the Yahoo Query Language platform they first launched late last year as part of their Yahoo Open Strategy. YQL is a SQL-like programming interface to all Yahoo data that can also support non-Yahoo data as well (think of queries that look like: select id from flickr.photos.search where text='car'). This week's release adds a set of new features called Yahoo Execute which begin putting in place more pieces of a powerful cloud-based development platform.