Drug use in running

Even people who are not interested in the Tour de France will not have missed the commotion the last few days. All this commotion centred around drug use or suspected misconduct from the leader wearing the yellow jersey. Lying about your whereabouts before the tour can get you fired as shown by the decision from the Rabobank crew firing Rasmussen who otherwise would have finished as the winner of the tour in Paris next Sunday.
This made me think: is there any drug use in long distance running? Of course drug use in athletics is a well known phenomena with one of the most well known cases that of Ben Johnson or the suspected use of Flo Jo although with her no proof was ever found.
I never heard of marathon runners that were caught using drugs. It might be the case that drug use is often used for either gaining strength or a fast recovery. The strength necessary for running a marathon can easily be gained by normal training and a fast recovery is not as crucial as with cycling were they have to be on the bike day after day for a few weeks in a row as in the Tour.
Another aspect might be the financial part: Of course the world class runner earn nice money but the figures have less digits than in Cycling or for example soccer. Think of the death of Miklos Feher (check out YouTube for the impressive images of his death) were there is some suspicion on the use of profen like drugs for fast recovery to enable player to cope with the full schedule with the large number of matches.
Maybe when less money is involved and it is more about the honour athletes tend to be more careful for their health.