Back in the 90's I used to use MLDBM as the database for simple CGI apps that didn't call for a full-blown RDBMS. There are some obvious limitations, but at the time it was a pretty powerful setup for simple applications.
It's amazing how few people seemed to understand that NoSQL existed long before Mongo's marketing team cashed in on the trend. I was using various NoSQl solutions before they were trendy.
