The days of giving guests a disposable camera for extra snapshots are long gone. Definitely opt for a photo booth instead. I was lucky enough to pick a venue with a booth built in. Yep, definitely helped me choose Lofty Spaces!
My Mom and I collected props for the booth during the months leading up to the big day. Right after Halloween, we hit the jackpot at a random thrift store: sailor hats, raccoon hats, giant glasses, flower headbands, cheetah ears, pig nose, etc. The funnier, the better. We put them in a box inside the booth and they were a hit!
Our plan for the backdrop was to have fabric-streamers in the colors from the wedding. In the shuffle of wedding-day, my backdrop I worked so hard on never got put up & a left-over-from-another-event black lace sheet was there. Of course, I was in horror when I made it to the booth, about an hour into the reception. I think our guests were having enough fun with props, so no one noticed or cared...except me! I'm getting over it :) Things happen, especially on weddings days!
If your venue doesn't have one, there are plenty of other ways to have a booth on your big day. Some wedding photographers offer that service, in addition to the portraits. You can also rent a booth for the day-of. Smilebooth specializes in photo booths for special events. (It's totally a dream of mine to own my own Smilebooth one day!) Their site can help you find a booth wherever you live. Your last option, if you're more of a DIY-er, be sure to check out all the great options people have shared on Pinterest. Any way you do it, make it happen. Your guests will love 'em!