Typically we have taken a presentation stand along with a large photo frame that I've added a chalkboard to. My wife used to write "Photo Booth ->" on it, we then upgraded it with some letters cut-out and glued to the board. After having it knocked down by people that just couldn't see the 2' x 3' sign in their way, we decided to try some new signage.
While at Michael's Crafts store the other day we found a couple of photo frames that were in the shape of filmstrips. My wife found some fonts on the computer that worked with the bride's invitation for our last event and added some additional messages in the top/bottom frames. We were able to hang one on each side of our booth, well out of the way, Added some red ribbons to match the bride's theme too.
I couldn't find the same frame on Michael's site, but found it on IKEA's...
7 (4x6) picture frame: http://www.ikea.com/us/en/catalog/products/30065679/
15 (2x3) picture frame: http://www.michaels.com/15-Opening-Mini-Filmstrip-Collage-Frame/fr0569,default,pd.html?cgid=products-framing-collage&start=1
We also used an old digital photo frame and loaded it with lots of fun booth pics and rotated our logo and some other messages in. Worked really well for catching guest's eyes and drawing the over. Alice, you may need to put your slideshow from your site on one of these, would work great. I think I'm going to order a larger (14" - 15") frame for just this purpose going forward.