In lieu of favors, we're going to be renting a photo booth. We will print out decorative notes for each table inviting the guests to take some pictures in the photo booth and bring the memories home with them

I was worried that guests might pass up traditional favors, but this way they can choose to use the booth if they want to. At the end of the night the bride and groom get a CD of all pictures taken during the reception
Re: Photo Booth - favors
We are also having a photobooth and considered using these frames as a way to double our favor with our escort cards.
This company offers the "T" style frame versus the "sling back" style. The "T" style lends itself much more readily to being used to do double duty as escort card/favor. Guests could find their name/table number printed on cardstock of your choice/pattern on one side of this frame, and then guests could slide their photobooth photo on the opposite side once they had their photos taken.
The acrylic frames also lend themselves nicely to any type of DIY idea you might have, from adding a simple ribbon to some sort of hot glue gun wizardry you might have!
Just a thought.