As for other kinds of intellectual property right, I'm afraid I can't really help you. It really depends on where you live. I would suggest you read the information on the USPTO website (US Patent and Trademark Office) if you are in the US, or the equivalent for where you live. There may be some information there on your rights regarding your designs.
1) File for a provisional patent (cost $110), this will get you a year of weak to moderate legal protection
2) design, mock-up and create a sales page for you product
3) attempt to license the product to a partner, in this case, a packaging or manufacturing company.
4) in the unlikely event anyone wants it -> profit
5) otherwise, go back to the drawing board, content in having pursued it.
Net outlays, probably less than $1,000, and perhaps 40 to 200 hours of work.
This guy's a wealth of information for this stuff, btw: http://www.inventright.com/ Also: Provisional Patent info: http://inventors.about.com/od/provisionalpatent/a/Provisiona...