How would you identify potential flaws in your code? Conducting a code review would make sure that:
1. Possible errors/exceptions are dealt with.
2. Proper design patterns and good coding idioms have been used.
3. Common logical errors are eliminated and more...
However if bugs were introduced by a human in the first place, then those self-same bugs could be missed during a code review. Human program-comprehension is not very reliable.
Now, what if there were a tool to conduct the code review? That's what Static Code Analysis is for. It involves the analysis of program code without actually executing it. Of course, unlike a human, a tool that automates the process of static analysis can't really consider design issues on a large scale. It can offer advice about certain basic design patterns and good programming practices but it can't go beyond that and look at the big picture.
There are plenty of great static analysis tools around. You can get a complete list here. If you're a C/C++ programmer, you might want to try out Cppcheck. Its been GPL licensed and has a QT application front end for those who don't want to get their hands dirty with the command line. :)
Wiki entry on Cppcheck
SourceForge Project site of CppCheck