Recently there are two: Fitbits and GPro. Both stock prices surged through the roof and crashed down.
If you have read my books such as Complete The Art of Investing, you should profit on these momentum stocks using Buy High and Sell Higher strategy. You need to protect your profit by adjusting your stops.
The momentum is caused by the publicity and the public who follow the trend blindly. If you looked at the fundamentals of both companies (now they're more reasonable), they did not justify for the prices. It is like buying a hot dog cart in NYC for a million dollar. Of course, you will sell a lot of hot dogs as long as you do not have another hot dog cart next to your cart. However, your investment may never be recouped. In addition, both are one-product company; it would be very risky if there is competition. Apple is one for Fitbits and I bet many Chinese companies are making products similar to GPro's. GPro's products could be a fad or will fall into a limited, specialized market.