I had initially gone to Target to buy a pretty notebook to use, but all the books they had would have been too big, leaving loads of empty pages. I was considering a spiral-bound notebook that would easily allow me to remove unnecessary pages* when packages of brightly colored file folders caught my eye. A picture of a hand-made mini scrapbook I'd seen on etsy flashed through my mind, and I spontaneously decided to make my own scrapbook out of those file folders.
I hit a few snags (e.g. when I realized that the scrapbook I wanted to emulate was made out of brown paper bags, not file folders), but it turned out great. See:

More pictures on flickr...
*This was a no-go because I didn't want to have a big spiral with a few pages on it... What, anal, me?! Ha!