Chaos Monkey is great, but it may be more pragmatic to start by injecting failures manually, rather than through an automated process. We do this with Failure Fridays at PagerDuty - https://blog.pagerduty.com/2013/11/failure-friday-at-pagerdu....
Forget Chaos Monkey, who's using Chaos Kong? That's what I want to know ;)
I use Chaos Monkey 3 times a day.
Chaos Monkey: https://github.com/Netflix/SimianArmy
introduction: http://techblog.netflix.com/2012/07/chaos-monkey-released-in...