A good example might be to start with your ten best selling products, put those on the front page, and then on those product pages you could have links to your next ten or hundred best selling products. Each product could have ten links, and each of those ten links could point to ten other products that are selling relatively well. Think about sites like YouTube or Amazon; they do an amazing job of driving users to related pages and related products that they might want to buy anyway.
If you show up on one of those pages and you see something that looks really good, you click on that and then from there you see five more useful and related products. You are immediately driving both users and search engines straight to your important products rather than starting to dive into a deep faceted navigation. It is the sort of thing where sites should experiment and find out what works best for them.
There are ways to do your site architecture, rather than sculpting the PageRank, where you are getting products that you think will sell the best or are most important front and center. If those are above the fold things, people are very likely to click on them. You can distribute that PageRank very carefully between related products, and use related links straight to your product pages rather than into your navigation. I think there are ways to do that without necessarily going towards trying to sculpt PageRank.