Simple. Useful. Light.
Regrettably, osCommerce hasn't been kept up. The last release was 2008 (see www.oscommerce.com), and it's now vulnerable. HostDime, an ISP, has notified their customers of the vulnerability and given them a date by which to migrate to a different eCommerce solution. It's too bad, because it =was= a decent solution for a non-techie to implement with only a little help.
There are no 4 star reviews.