Here's an idea adaptable for the end of a mission trip or any youth trip. Here's what the poster at Flickr says about the photo: "This was pretty simple and straightforward. This group had spent a year together in learning, small groups, mentorship, and fellowship, not to mention the year they spent doing their youth ministry work. We equated that to a "road trip" type spiritual pilgrimage. So we asked them to write God a postcard chronicling their experience. If I had to do this one again I'd probably make some postcards with various pictures. "