I've done 2 Fulls and about 15 Halfs. I usually keep the medal around my neck until I get back to my hotel. Once I shower and change, it's off for good. They all hang on a curtain rod in my bedroom.
When I ran the Chicago Marathon I may have worn the medal on the plane going home the next day. Looking back, that was a pretty douchey thing to do. But I saw lots of people in the airport with them that next day. I pretty much hate myself and never give myself any credit for anything, but I was proud to cross the finish line for the full marathon. It is really hard.
I have a 26.2 sticker on my bumper. So what.
I love the big city half marathons. I want to do the Philly R&R next year. I barely need any training for a half. Just diet for about 10 days, drop 5-7 lbs, mix in a few mid-range runs and I'm good.
I also want to do the Marine Corp Marathon in DC eventually. But I just don't have time to train for another full.