To convince my team mates of the usefulness of design-by-contract, I am looking for well known examples of realistic systems that were built using design by contract. Pointers to realistic, critical evaluations are appreciated.
In other words: what is the best example of a system successfully built using design-by-contract?
If by "contract" you mean function specifications expressed in a formal language as preconditions, postconditions and invariants, then part of the software embedded in the A380 was specified using design-by-contract. The verification was done statically using the principles of Hoare logic, as implemented in the tool Caveat, instead of dynamically using run-time assertion checking, the more popular approach.
Eiffel Software mentions some success stories of the customers that apply Design by Contract method in their products.