In addition to the ruby-frontbase project to provide Ruby access to FrontBase databases, Rails now has an ActiveRecord adapter for FrontBase as well so that you can use FrontBase as a back-end for Ruby on Rails development. In addition, FrontBase changed their licensing model last month and the database is now 100% free to use. It supports Mac OS X (Universal), Linux (RedHat, Mandrake, SuSE, Debian, YellowDog, IBM S390), FreeBSD, Solaris, and Windows NT/2000/XP. http://www.frontbase.com