Is the one you have with you.
Just got an Americano from the Starbucks drive-thru, and as I was waiting the rain began collecting on my windshield. I've always liked the look of raindrops on the window, but Ive never had my camera ready. So, today I just took this photo with my Droid X. I'm pretty impressed with this "phone", if we can still call them that nowadays. They're more like a small computer than a phone. The one thing most of them have in common though is that they have a camera. So the next time you see something picture worthy, just remember that the best camera is the one that's with you.