A little company called Fileability may have found a nice little niche for Mac productivity. The product is called XBase. It's a simple to use database creation application. It allows you create forms and push data collected through those forms to a database. Very nice, and simple!
Here's a thought for you, but it probably goes against the iPhone developer rules. Build a version that creates iPhone data collection applications. That could prove VERY useful in the real world.
Hmmmm, that's not a bad idea at all! You'd need to actually generate code that could be compiled as a native iPhone app so it wouldn't break the rules. If you had a library of data collection patterns, for UI and databases, your database application could generate code, tie it to the library, and then build the application for the iPhone. I know, overly simplistic in thought, but I think doable.