Christian Louboutin recently won the right to trademark its red heels, spurring questions about what else can be branded.

Well, actually, a lot else—sounds, shapes, symbols, and even colors can be trademarked.

Don't confuse the term "trademark" with ownership of color though. Trademarking a color simply allows a company to use a particular combination and shade of color in its own industry.

Target can't sue Coca-Cola for using a similar red, because they are not selling competing products. Following the same logic, when in 2008, T-Mobile threatened to sue Engadget for using "its" magenta, the tech website sort of laughed it off.

So, how far would a company go to protect its brand?