A good example to look at is banks. Banks are eventually consistent systems. An ATM allows you to withdrawal funds (to a set limit) even if it can't communicate with the bank. However, because banks keep full audit logs of all transactions (immutable data), they eventually discover that you took out too much money and charge you an overdraft fee.
This isn't really relevant to the pocket watch problem. This only works because the bank doesn't care about over-committing a finite resource (mostly because they can charge you that fee). My company processes transactions for prepaid credit cards, so any money that is overdrawn is essentially lost - it's important to understand the characteristics of the problem and that there really is no magic anti-CAP bullet.
http://en.wikipedia.org/wiki/Overdraft