When designing a database in the “conceptual” or “logical” design phase, the designer need not be concerned about what particular database engine will host the design.
Most developers find themselves favoring one database platform over another.
Many developers, for example, are comfortable with ORACLE, MS-ACCESS and SQL Server.
Recently I’ve begun thinking about open source database platforms.
I discovered a free download of the PostgreSQL Windows client database software. Here is the link http://www.postgresql.org/download/windows
I found a couple of posts from people who have used it as a back-end to Microsoft Access.
A database platform, free to us with no licensing cost; many customers might choose a product with these characteristics.
Couple that with a free redistributable executable of ms-access makes a compelling case to a small business.