Yes, open source database software is a viable option. Open source databases can provide the same features that expensive commercial database solutions offer, while often being more reliable and cost-effective. They also offer increased flexibility with customizations and give users access to a wider range of data types than traditional RDBMSs. Notable open source databases include MongoDB, PostgreSQL, MariaDB and CouchDB. Additionally, many cloud providers like Amazon Web Services offer managed versions of popular databases such as Oracle and MySQL that allow for easier administration.