Back in the early 80's video stores also rented VCRs. Now there's 3D films on blueray, but many people don't have a 3D TV. So rent out a PASSIVE 3D tv (LG makes a good one) with a half dozen glasses. Kids parties would be a natural (or 3D porno for adult parties).
Also if he is not doing S-8 to DVD transfers and picture scanning he's missing out on a big advantage, as his customers would not have to risk mailing their orginals.
Another idea would be to get a WIDE assortment of gizmos from DX.com. Most of the items could be kept in a stockroom, if he had a few kiosks for customers to browse. Use the display for new items and kids toys.