Does the e-commerce module (version 0.9, I haven't had time to upgrade to 1.0 yet) have the ability to set temporary discounts for a product? I'm thinking along the lines of the usual <<insert holiday>> specials in which the original price is quoted but crossed out, and the special price is shown. The product template does include this feature, but I haven't seen any method to set a discounted price on a per-product basis.
If this feature isn't available yet, what would be the best method of adding it? I'm not particularly familiar with the e-commerce module's APIs for adding custom behaviour.
You could also add Start/End dates for the sale.
However, this requires setting each product's price manually.
For a more advanced approach, you would likely have to create your own completely separate ProductDiscount class that allows you to employ more advanced rules and perhaps the ability to apply the same rule to multiple products. Then parse those rules in updateCalculatedPrice.
The complex pricing documentation is a bit vague, but it might do almost everything that I want. The one thing that's missing is being able to display a name for the special and the deadline on the product page (e.g., "<<event>> sale ends <<date>>").