The file Recent.lst stores a list of the most recently used sources.
If you are a new user, it will of course be empty.

You can save lists of recent files and also load them from Soundshaper. (They can be given any name, provided they have the suffix .lst or .txt .)
Although the Pool lists are intended as lists of project sources, 'recents' lists can also act in this way.

You can also edit the file Recent.lst (or other 'recents' lists) manaually.

R.F. June '13 