I've been away for home for a total of something like six months in the last two years... if I have a rental car, I try to hit the nearest air museum and of course do some flying. I really got a lot done in San Diego last summer, as I was on a "normal" schedule for eight weeks: air show, air race, vintage auto race, trip to Palomar Observatory, kayaking in La Jolla cove, two air museums... and of course my tailwheel checkout and some fun trips in the Champ.
I'm in Chicago at the mo' , working nights for a week, no car... but I took a train and bus out to Rockford yesterday and was rewarded with a wonderful visit with some folks I knew only from another web board, and even got to fly their C-140 on skis.
Tomorrow I'll most likely go to the big museum in town, and before the week is out probably the Sears Tower and perhaps a trip to Meigs to lay a wreath or something. Might meet up with some other web-forum buddies who are also in town this week.
Anyway, the key thing is to turn off the damn TV and go out and do something... anything!
Take some time to study up on what there is to do where you're going; don't wait until you're in town to sit down and come up with ideas.
But doing some flying, even in a crummy rental, is the best, especially if you are far from home and unlikely to ever fly out that way from your home 'drome.
Got my fingers crossed for a possible trip to Dubai in the next year... I'll live on dates and water and use the fat per diem to try to do some flying there.