If you haven't seen this fun site, you've got to check it out! It's called Big Huge Labs and that's where I made this:
How fun is that?!? I've made a similar grid of images in Photoshop, but this was really quick and easy, and not everyone works in Photoshop... so be sure to visit the site, it's free, but they welcome donations, too. And thanks to Hanna for information on how she made her grid, which you can view at her wonderful site, iHanna. Have a happy weekend, NOW GO MAKE SOMETHING!