When editing or adding products to your PowerCommerce store, you can specify “merchant-set pricing” or “shopper-set pricing”. The shopper-set pricing option allows the shopper to indicate how much they wish to pay for the item. You can set the minimum and maximum price to be sure their bid falls within that range.
This can be a great tool for a product that is used as a fund-raising tool, allowing the shopper to “donate” an amount that is most convenient to them while still receiving the benefit of the product as an “incentive”.