Facebook did it once. First by marketing to college students for the original product (Facebook), then by buying the next big thing (Instagram).

I don't think they're doing it again though, many recent acquisitions (starting from Oculus in 2014) are VR/AR based, and AFAIK they're growing the core Facebook product instead of launching new ones.

My thoughts exactly. My impression is that the key is to get in early while a product's value is rising, then cash out at the last possible second for maximum gain. Then, once you're financially established, you can throw portions of your wealth into equity in later iterations and repeat the cycle.