The main problem with ancap is that there's nothing preventing a violent gang (a new government if you will) from forming, because everyone else is being so peaceful, and if everyone else stops being peaceful, then it it isn't ancap any more - its just regular anarchy.

Ancap will only work if there is some force to stop people from conducting acts of violence, preferably some force that isn't corruptible. So, until we have open-source peacemaking enforcement droids no such utopia can exist.