As a research scientist I don’t sell any products or services. Some scientists offer their skills to different companies as consultants but I don’t fancy doing that just yet.
I suppose we all have to sell our ideas in a way… when you want to publish results you have to convince other scientists that they are A) real and B) of use to others. You also have to sell your project ideas when you apply for funding. The way that you explain them and their importance is vital if you want a million pound grant!