I've done a bit of research, and have begun to build a website, (and rank for it in google) that deals with the selling of Customizable cocktail umbrellas - in such that you may buy them with predefined text ("Happy 50th Birthday, Steve!"), or pictures, etc, printed on the umbrella.
Doing a bit of google analytic research, the numbers seem good enough for me to find a supplier - someone who can supply me with what I need.
The initial investment lies in the 250-750 range, but if and when all goes well, it shall definitely pick up.
This is another website in a long series of successful websites dealing with simple product ideas.
Please let me know if you think you could get your hands on a supplier, or a supplier yourself, of my very small niche.