Examples: Backblaze [2] and Basecamp [1]
Anyone can shoot to be a unicorn [3]. Takes something else to be comfortable with a daily grind (but a grind you enjoy), reliably yet without much fanfare meeting your customers' (mostly static) need.
[1] https://m.signalvnoise.com/the-deal-jeff-bezos-got-on-baseca...
[2] https://news.ycombinator.com/item?id=15074289 (/u/brianwski, Backblaze cofounder: "Finally, Backblaze is profoundly different than CrashPlan in that we never really raised any bank financing or VC financing. We're 90% employee owned, and there are no deep pockets. CrashPlan raised something like $150 million which comes with "pressure to grow fast or die". Backblaze is free of any such pressure, we own our own fate.")
[3] https://www.youtube.com/watch?v=BzAdXyPYKQo (nsfw language)