A few months back, I tried to make a case for code inspections. So I was happy to find the following post on Michael Swanson's Blog at MSDN.
Michael Swanson helped manage the development team for NxOpinion diagnostic software. NxOpinion is a medical decision-support application. The team used some techniques from Agile, but also implemented formal code reviews and code metrics. During development, pair-programming (one writing code, one reviewing the code as it is written) was used. But they also held formal code reviews. They did this to educate people about the coding standards that had been agreed upon and to focus on improving the functionality of the code.
On a daily basis, an automated process would check out all the code and calculate the metrics. These metrics were stored as checkpoints. They were also used to pinpoint which code was a suitable candidate for code reviews. The higher the complexity of the code, the more likely it would be a candidate for a review.
A definite read if you're interested in code reviews!
In the comments on this post, you will find links to various (freeware) code complexity tools. I can recommend the community version of DevMetrics. I'm using it in my current project to pinpoint candidates for review and/or refactoring.