I would consider any trip that's primary purpose is to achieve miles a mileage run as long as it meets the following condition:
The benefits (miles, status, etc) gained are greater than the cost of the trip.- otherwise, you are paying to go to your destination. Obviously, the above equation is unique to the individual (i.e. how do you value status?).


I went to Europe for the weekend. Left on Friday, arrived on Saturday morning, visited museums all day Saturday, stayed in a cheap hotel, and flew home Sunday. By my calculations (include hotel/airport parking/ground trans in Europe- but not meals b/c I eat regardless of the continent) I came out $100 ahead plus I'll be gold by the end of the year. To me that's a mileage run- albeit not as hardcore as a trip to the west coast which I showed up and stayed in the lounge for 3 hours. Funny thing is- that I got questioned like crazy by security for the Europe trip (in which I actually visited my destination)- but nobody thought twice about my west coast destination for three hours.