[bluejeanz]

I'll have to try that. Your way is cheaper than mine.

I use Cascade Plastic Booster that I found in the grocery store. It comes in a tube for about $2 (label says 'recommended by Tupperware and I also saw it in their catalogs). You put a few tablespoons of it when you run your dishwasher. I don't have a dishwasher so I just put a small amount of it in the container I want to clean, pour boiling water into it, mix it up and within a short period of time the stains are gone. You could throw it in the microwave to heat up the water again if the stains aren't all out the first time.

I don't often have to use it. I found that storing tomato sauce-y items in containers don't leave stains but warming them up in them does. Additionally when there's fat content in it.