He came to China to study Mandarin and in the process he created "Bejing Sammies". Entreprenuers always fill a need and sometimes an empty stomach.

Listen to an entrepreneur who learned in the trenches. Where East Eats West: The Street Smarts Guide to Business in China by Sam Goodman. Each chapter is 3-4 pages(obviously his target audience wants just the meat in their reading material!) See the Top Ten Biz Mistakes and  follow the link for the video. The most interesting comments are regarding the opportunities in the second tier and third tier cities.