Amazon

Many challenging technical problems to tackle as an employee. They give lots of room for you to shine, but also rope to hang yourself.

It's a very dynamic culture and promotes the best solution at the time. This could be bad, though, since it also means a lot of bad solutions are introduced before the best comes out.

Be prepared to move groups every year or two. You will get managed out if you're in the lower end of reviews. Middle management changes direction too much. It's a very operations-oriented culture, which means pager duty for everyone. Depending on the group, you could spend a lot of time fire-fighting.

Gain some stability in management's own hierarchy. It's like a revolving door every year, and this trickles down such that teams have constant churn.