Houdini's default database is a portable performant SQL92 compliant open source database, therefore, your data is easily accessible by standard SQL tools.
If you are a SaaS client we can provide you with your data in the same portable SQL92 compliant open source database. Just about any product can access the data. You can even use free tools such as Toad or DB Visualizer to access your data.
The benefit of this option is your data and all its relationships remain intact. Unlike flat CSV files your data is just as it was when you were using Houdini. This is the quickest and most reliable means to move relational data from one product to another.
You can use the above tools to export your data in many formats e.g. XML, CSV, SQL etc.