Better than getting the filtering done real-time would be to not have filtering at all, but rather to add explicit sort keys for the artist, album, and song title fields

This was another idea I was also thinking of. I was avoiding mentioning it because I thought no one else would be keen on creating some non-standard approach to this. However, if an established ID3 tag already exists for this purpose, I think support in the player would be an excellent idea. Of course it involves extending the database structure to include this additional field.

And to properly use this ability it would be nice to have a tool to populate it with the correct data. Some scripting or regular expressions should be able to handle this.

Bruno