Organizing screenshots into collections

Hey! I just recently found out about Skitch and I'm already using it a ton. Awesome service and program. I just have a suggestion for a new feature I'd like to see. I think it would be really handy to be able to organize screenshots into collections (you could call them 'photobooks' or something) and then you could send a particular photobook url to a friend and they could see all the screenshots in that photobook. This would be mostly useful when you don't want that person to see your other pictures.