I love samples, particularly when its a consumable item that I would normaly buy in person (make up, soap, lotion, shampoo, etc.) That way I can try the item and make sure I like it. It's particularly helpful for me b/c my skin is more olive toned than it is white or black (if that makes sense!) and I have so many allergies that even some 'safe' cosmetics/soaps bother my skin. So, if I can find samples of a product I love to buy one or two occassionally to see how I like it!
PS- will you be selling sample sized face powder? I'm looking for some natural powder, but would want to try a sample first to check match/sensitivity :)