I've got a number of old apex classes that I am planning up updating to use a more recent version of the Salesforce.com API. Of course, it would be better still if I could retire some of these classes. I know they haven't been updated in years. Is there a way to determine when the class was last run? I don't see anything like a "Last run" property when I edit one of the Apex class views. Is this information available anywhere else (like maybe Eclipse)?
edited to add The metadata API does not even have "date last modified" for an Apex class. "Date last run" was too much to hope for.