Welcome to the Q&A Forum

You could write a positive article about them or provide them with a testimonial that they can add to their site.

When someone embeds your video it should not pass link juice because the code doesn't include HTML for a link. I checked the embed code for one of SEOMOz's whiteboard friday videos since they use Wista and all I found was a link to Wistia.com in the code.

An alternative option is that you could turn off embedding on the video so that people would have to link to the page on your site where the video is located.

Option 1 would send more link authority (i.e. "link juice") to your specific product pages where the conversion will take place. This is also known as a flat site architecture (which is generally recommended) where there are fewer levels in your site hierarchy. As long as there are not an overwhelming number of products (which could hurt the user experience) option 1 is better for SEO in my opinion because the product pages will receive more link authority and have a better chance of ranking well in search results. If you have more than say about 20 products on each category page, then option 2 starts to seem more attractive for two reasons. First, the user experience is worsened as the page clutters up with too many options (see The Paradox of Choice) and also each additional link on the page will dilute the amount of link authority that is passed to each individual link.