Reselling products is a great business model. We see plenty of affiliate marketers making money off of selling someone else's products. On the other side of the fence, there are endless amounts of "gurus" selling their knowledge to people that will then essentially be passed down the line when those people make their own "guru" product.
A lot of the commerce taking place on the web has been designed like that of a pyramid. A great product is created, then passed down the line, either as an imitation or repackaged in the form of a Reseller's program.
A good example of a business that creates this type of value down the line of consumption is PHP Dir Submit. Essentially, this site sells a "business in a box," which allows purchasers to open their doors as a service provider thereafter. This particular product is an article directory submitter, but I'm sure you can see how this type of business infrastructure can work in many types of verticals.
If your passion lends itself to a multi-tiered sharing system, tap into it. Be careful, however, that you don't cross into being an MLM or a Ponzi scheme. At the core of the business has to be a valuable product that is actually well worth the purchase.