I would like to collect some ideas what features or plug-ins might be helpful to create something like a "sales corner"? Tiki Wikis run be non-profit organisations may want to add something they already do when they have a printed magazine or newsletter, a sales corner. Some space reserved to sell small amounts of items like self-published books, older magazine issues, books that have been reviewed, CDs or (more historically ) t-shirts and stuff like that. Doesn't have to be fancy. This is not the prime directive for such a Wiki, just a welcomed by-product that helps to keep the Wiki (and the organization) up and running.
There should be a number of items that can easily be entered by non-admins, images can be taken from the file gallery. A number of these items should be presentable in one page, say a matrix of 5 by 5. Users should be able to click on a button to buy, and at least a rudimentary bill should be created for the user, VAT calculated, S&H added, and some form of alert to the org (either e-mail or aggregated info that can be easily viewed). No need for high fashion layout or bills management. KISS (keep it simple and straightforward).