Digital Scrapbooking, Free Backgrounds

Personally, I think the wallpaper store idea that I discussed in my last post is the best way to find backgrounds for your scrapbook. However, there are some places to find backgrounds specifically designed for scrapbooks. The places i checked out were Smilebox and Picaboo, based on some search results. I thought that Picaboo seemed easier to use and they have a tour that shows you what to do. Both sites have many backgrounds to choose from, though. I like to just print out the background and glue my pictures on the page. However, with these sites, you can digitally insert your pics right onto the page and send them or print them out if you so choose. Which site do you guys like best: Smilebox, Picaboo, or some other site??