Thanks for the pics, that looks like a great multi-day option for those (me) not wanting to mount traditional saddlebags with racks or brackets. I'm also looking for a smaller day-ride system. A backpack holding tools, tire repair kit, camera etc is not working out for me. This Giant Loop rackless piece looks like it might fill the bill (and will hold their 2L fuel bottle).
Hmm can't post links yet. You can have a look by searching Giant Loop Mojavi.