Since virtually all of my experience is in academia and I have basically succeeded in getting a tenure track position, I feel ill equipped to advise these students in making decisions about their future and showing them alternative role models.
Where can I get the experience and resources to show students that would potentially benefit from considering alternatives to an academic career that high quality alternatives exist?
(NOTE: I am in the natural sciences so answers specific to science would be great but if a cross-discipline answer exists, that would be ideal)
Here I briefly describe two ideas regarding to what a professor can do in this situation.
Keep contact with former students: Frequently, professors establish relationship with students during classes or during an undergraduate or master's thesis. Probably, maintaining these relationships after students graduate may give you some interesting points of view regarding jobs in the industry. You can just send an email to a former student in order to ask her about her job or you can invite former students to give a talk in one of your classes.
Establish relationships with actors in the industry: If students are required to take an internship, you can contact institutions that receive students for internship and suggest those institutions candidates that you know. I suppose that if you are able to refer to them good students, you can continue the relationship with those institutions.
Another alternative would be to engage in professional activities in the industry. However, this depends on whether you are interested in working as a consultant or something similar.
In our university, we have good experiences with inviting alumni who are now in industry to give career-oriented talks. The students know that the person giving the talk was in the same study program as they are now, and I guess just this alone helps them to see possible role models in the persons giving talks. The best talks are when alumni not only report about the technical points of the project they are working on, but also give a more personal account of their development towards their current job.
These talks are organized by the alumni organisation of the study program, which certainly helps getting the contacts to potential speakers. But I can also imaging getting these contacts in other ways.
My university is only engineering, but I'll try to answer. The administration is working hard to allow graduate program internships (coops), as they are successful at the undergrad level. The other angle is that there are two flavors of master's degree: professional and research. The former is not an academic career path. Most students already have an idea where they want to go when they register, and the ratio is about 4:1.