I've recently been playing with the
ecommerce module for a work-related project.
Suffice to say, I think it rocks.
It tried it about 6 months ago and there were about 3 modules - now there are about 3 pages worth when you print them out!
It handles a bunch of payment API's from Paypal and Worldpay to ones I've never even heard of. It handles different product types from tangible to media and electronic to generic products. It has a cart. It has stats and invoices. It has recurring products. It has an option for users to purchase "role" upgrades (eg, you could go from being authenticated to "subscriber" which might allow you to have a blog, etc). Its pretty darn cool
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