This was around earlier this spring as a $750 all-in return fare but was limited to only Tues and Wed. Looks like it's good for all days now. JFK-Stansted. Travel must be completed by June 2. For those who love May in London not a bad deal. And, yes, MaxJet does have a FF program.
https://www.maxjet.com/search.do?req...ge=search.page
Also, here's the earlier thread with more info and opinions regarding MaxJet.
http://www.flyertalk.com/forum/showt...ghlight=maxjet