There's another thread on this from a month or two ago, you may find some information in that one too.

I use to do it, booked on two flights from Detroit to Boston on the 5 and 6 pm flights on Friday Afternoons. My girlfriend lived out there, so I flew out for the end of every week (my workweek then started on Saturday).

Both flights, bumpped every single week that summer, got $200 from each airline, money for food, and there was another flight in a couple of hours. At the time (it was a while ago) I made more on Fridays from getting bumpped then I did working.