Dan - I second your motion to avoid shuffling stuff into and out of the database. Ben and I have talked about doing file storage the same way, i.e. store user files in the file system rather than in the database. This would be more efficient even with "real" large objects (rather than my kludged large objects). Would need to develop a repository for binary objects, have all modules use it, etc.
The only reason to stuff the stuff into the database, as far as I can see, is that InterMedia can index it for searching.
