My best recent award was AMS-HKG-CGK on CX First using AA miles. I was the only customer in first, and had two FAs at my service. Great food, excellent F seats, and great service.
Best all time use of mileage was a NW RTW award in 2006. 220K. About $300 in taxes. Spread over 11 months, 6 continents, and all in Biz or FC. Those were the days.
Flew KE, AZ, AF, OK and CO. I wrote about it in Expert Flyer, March 2008.