I am working on a site (to see work in progress http://users.rcn.com/shawnsears/josh/index.htm )and I had an idea but my actionscript is not near good enough to figure it out...so please help if possible

On the main interface to 'dot formations' will take you to the photo page for that category...no problen (just haven't gotten that far in the process) but what I had in mind was this... when the user click on a dot to see a photo; that dot, which corresponds to that picture will fall down to the bottom of the screen as a denoteing a previously viewed photo which can be viewed again whithout having to hunt through the random messes of dots while leaving the unviewed photos in the original formation...I can figure that part out but I want the previously viewed photo dots to be there if the users goes to antoher screen and then returns to review photos they had previuosly seen so they don't have to go hunting for that special pic.

any ideas? I hope I explained my problem well enough.