Ask HN: Good Mobile/Online Diet Planner or Calorie Counter?

I'm starting Day 1 of the Gold's Gym challenge today, and I need to get diligent about tracking my food intake and exercise plans. I've used "Calorie Counter" on my Droid in the past. I really like the fact that I can scan a bar code directly, and that its got some basic food diary features, but it doesn't allow me to enter the odd-ball portions that I have to use for the various Challenge food plans.

Do any of you use anything like this for diet planning or calorie counting? Ideally, it would work both on my mobile phone (for the great convenience of bar code scanning and on the road usage), but also have a web option as well (way more convenient to adjust things this way).