When assets should no longer be used after a certain point (e.g. because the usage right has expired), it's usually difficult to find out who downloaded those assets in order to notify the people in advance of the expiration date.
This plugin looks for assets that meet a certain date-based condition (user-defineable) and aggregates a list of recipients for each expired asset, who are then notified by e-mail. By default, the download statistics are used to determine all users who have ever downloaded the asset. However, you can also specify your own method to determine the persons that should be notified.
For example, a small extension of brix:anura makes it possible to request an e-mail address during the download, all of which will then also be notified.