I find "Don't reinvent the wheel" to be a terrible idiom.  Think about the wheel for a moment.  Is the wheel on your bike the same as the wheel on your car, or on a train, or an an airplane?  Of course they're all different!  The wheel has been reinvented thousands of times, and we're better off for it!<p>Yes, it can be worthwhile to borrow successful concepts from other disciplines.  But in many cases, the concrete implementation NEEDS to be reinvented in order to apply the abstract concept to a new purpose.