That'll be nice function. I think it is not hard to add paypal function. But I would really like to see a ecommerce function where:
People buy prints, but the sales are sorted by member, and the admin collects all the sales money, distribute the commission (configurable in admin setting, 15% or 100%), to the members by check or paypal manually.
This would be a little complex as it involves in additional coding in managing sales, but once it's done, it can be used for single user PP, or multiple user PP.