An example that I love is how Humble Bundle let's you pay for video games. If you look at their slider model it's the best I've seen and would work perfectly with weighting an action score for a stock.
**If you're interested in seeing it go to humblebundle.com, scroll down to "Pay What You Want" and there's a dropdown called "Choose where your money goes". It allows you to weight the compensation between the developers, Humble Bundle, and charity.
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