I'd love to do a few different hobbies...one is weird. I'd love to do theme traveling. I'd choose something interesting to me and my husband and we'd plan travels around that. Like pizza? Map out some pizza locations that got rave reviews and plan a trip to visit those spots to eat.
Or how about waterfalls? That would be a cool one too. It just gets expensive with gas, tolls and hotel spots, plus the eating out at restaurants.