I thought this should be cheap, but realized that it is going to be quite expensive ... between 100-150 pounds for a return ticket via bus. Is there any other affordable way (via bus, train, ...) to commute between the two cities? I imagine there must exist a third city that I could cheaply travel to/from Cambridge and Sheffield and somehow break the costs. But not familiar with the country.
Even if one travels from Cambridge to London and take the bus from there to Sheffield, it would be several times cheaper than the direct Cambridge to Sheffield trip. But that means at least 4.5 hours extra time being spent on the trip.