patent attorney, angel investor, malevolent dad
... wishing there was another answer here!
Cisco, NetApp (yes, they were startups too, once)
most frustrating: it occupies your entire life
most rewarding: it occupies your entire life
thinking they will find customers just because their idea is so cool
1. People don't want drills, they want holes.
2. It's NOT so that "if you build it, they will come."
3. It's (almost) never a mistake to take more cash than expected, in a funding round.
... arriving with the next Angry Bird.