I have one for you. This was one of my best business ideas of all time. It made me good money very quickly. Unfortunately, it was somewhat illegal, if you know what I mean.
My friend and I used to visit Canal Street in NYC often, about 25 years ago. Back then, the shops down there sold knock-offs of just about anything, from handbags to stereos to jewelry. We were never really into anything other than watches, so that's what we went down there to buy. They had a bunch of different brands and some of them were cheesy, but the TAG Heuer watches looked great. Very authentic. And for $25 each, they weren't a bad deal, considering they kept time as good as any other brand of watch that I've owned.
Anyway, after buying a few of these watches and wearing them to a local college I attended, I noticed some interest in them from the other students. Right there, I saw an opportunity. The next time my friend and I visited Canal Street, I bought a few extra watches. When I brought them to the college, they sold like hotcakes. So because of this, we continued to visit our favorite watch shop to buy, but because we were frequent customers by this point, I was able to haggle the price of each watch down to $7. When I sold them at the college, I charged $20. After a few weeks, I was able to make a handsome profit.
The best part of all this was that I had one customer who was from another country. He loved the watches and he would buy about five from me every time I saw him. He'd ship them back home to his friends. I actually didn't care what he did with them as long as he continued to buy them.
Eventually though, my friend and I saturated the market at our college and we weren't able to find any more customers. That's when our endeavor stopped. It was good while it lasted though.