photographyawesomesauce.com: Leave a discount that gradually decreases over time. If I leave their gallery up for 3 months than they might get 20% off the first month, 15% the second and 10% the last month before it goes offline.
It’s always a good idea to copyright your work and a good way of doing so, is to embed your copyright information into your image metadata. To do so, Press Ctrl Alt Shift I (Mac: Command Option Shift I) or go to File > File Info... to bring up the File Info panel. Then click on the "Description" tab and enter your copyright information on the appropriate fields.