Next Step for the Library

I know there are a lot of good suggestions for the Library out there, but most I've seen require some sort of database, requiring more time/resources to develop.
One idea that I hope would be easy to implement would be the way 1by1 does it's media selection:
http://mpesch3.de1.cc/1by1scr.html
It shows a directory tree/explorer window and you can select everything (recursively) in a directory. This shouldn't be too memory intensive, should it? No need for a database as it could be read at access time, but it might get slow if there is a large directory structure underneath. For the record, the whole download of 1by1 is 119k.
One idea that I hope would be easy to implement would be the way 1by1 does it's media selection:
http://mpesch3.de1.cc/1by1scr.html
It shows a directory tree/explorer window and you can select everything (recursively) in a directory. This shouldn't be too memory intensive, should it? No need for a database as it could be read at access time, but it might get slow if there is a large directory structure underneath. For the record, the whole download of 1by1 is 119k.