Well it used to be that you get 5000 or 9999 Delta miles for each rental at Budget but hey, you gotta take what's given.
Weekends seem to offer the best rates. The cost of the miles is about a penny a mile so it's a pretty good deal.
Check out your city and the promotion here.
This promotion doesn't expire until December 31st.
PS: Reports are that non medallion members are receiving their miles as well. Enjoy! :)