Geekage One thing I forgot to add, your time is valuable, even if this is just a hobby. Make sure there is a reasonable markup for your model prints. That doesn't mean you cannot do the cycling community favors, and try to keep the cost low, just make sure you figure out how to compensate yourself.
And one last thing, Shapeways is a service provider, they 3D print stuff, that is about all they do. The other materials that cannot be 3D printed are subcontracted out to other firms. They also provide a marketplace for you, but mostly so that they can advertise their own services. They cannot provide additional hardware with their 3D prints. I do know for a fact that there are many designers on Shapeways that buy their own prints, add whatever they need to add to them then resell those completed items on their own websites, so it is doable, if you want to invest the resources to build multi-component items.