You really found a good one! It does not appear to work on codeshares and has other restrictions, but, when it works, it comes up with a fare of $188.13 + fees and taxes. The funny part is, there don't ever appear to be fuel surcharges on fares booked with this promo code, whereas, there are on the same itninerary w/o the code.

By looking at the fare and notes, it appears as tho this is to get previous customers/agents back to YX.