The cheapest would probably the classic mileage run on the train between FRA and ZWS(Stuttgart Railway Station). You get 4000 status miles for every round trip in buusiness class, i.e. you would have to do 5 returns to reach the 20,000 miles you need. Same day returns (of which you could do a couple a day) are EUR106 each, weekend returns (with saturday night stay) are EUR66 each. So it would basically come down to EUR330-EUR530.
Of couse, if you could get hold of a non-European mailing address, you would only be 4000 miles short of FTL.
Has anybody out there any experience with nesting the cheap weekend fares between ZWS and FRA, e.g. two FRA-ZWS-FRA and one ZWS-FRA-ZWS, which would give 3 returns a weekend.
____________
edited to correct spelling mistake
[This message has been edited by yogimh49 (edited 07-02-2003).]