A very good startup intern opportunity - Intern PacketZoom Employee Review

As an intern, there were various learning opportunities. If you are interested in computer networks, you can rest assured that you will definitely learn how networking is done. You can be exposed to various stack of the technology and also how a startup functions. Programming languages ranges from Frontend to Backend Languages (includes Golang too - if you are keen) Feel free to ask questions. Everyone there are open to sharing!

Downside? You would probably have to be a fast learner if you want gain as much knowledge as possible.

Very nice team, family-like atmosphere, interesting technology and ambitious vision. Work time is flexible (goes both ways, but I list as Pro). You're going to learn a lot about mobile ecosystem, network stack, data analysis. Benefits are very close to top-level big companies. Next to the office there are plenty of good restaurants, and delicious donuts.

Work can get really intense at times. It's a startup so it's expected, and it's on reasonable level.