I like the video and comments Mark Graban posted on his Leanblog.org about no problems being a problem. I especially like the part where the speaker says that if there are no problems, there is no need for managers.
I worked with Mark Rosenthal of TheLeanThinker.com years ago when we were both at Genie Industries (now owned by Terex). We get together from time to time, and have some lively Lean conversations. He poses an interesting question about how airlines respond to abnormal conditions.