Tired of the double secret probation crap....... AVIS code.
note: borrowed from another site

1. Go to: http://www.avis.com/car-rental/avisHome/home.ac

2. Enter destination and WEEKEND dates

3. Enter Coupon Code: TUEA002

4. Select a car size from compact to full-size. Prices displayed will be adjusted on the next screen. Make sure to select "Pay Later" in case you want to cancel.

5. Confirm the reservation (no credit card required)

Note: Coupon isn’t valid in Alaska, the New York Metro area, Canada, Puerto Rico and the U.S. Virgin Islands. Must be for rentals BEFORE June 30, 2013.

Note 2: It says Canada not included but it seems to work for me anyways cost $6.73 for two days.

Note 3: On check out, it's actually a full $80 off, which means anything up to full-size is free.