In Flanders Fields Museum, Ypres, Belgium

If I were giving awards for souvenirs, this bracelet from In Flanders Field Museum in Ypres, Belgium would win.
When you pay the entry fee for the museum, you receive an electronic bracelet that not only grants you entrance but then allows you to personalize your visit. Upon entry, you visit a kiosk and input your age and gender. Then as you go through museum, there are interactive points where you touch your electronic bracelet to receive a story that someone like you at your current age would have experienced at that time.
Stories were from both sides of the war. The first one that I heard was of a German woman, then later a Belgium woman. They spoke as if it were current time, happening to them now. Along with the rest of the multi-media displays made the museum very personal, compelling and heartfelt, impossible not to cry, really.
It was good for the entire day, allowing you to leave and return. And then at the end of the day, you are welcome to keep the bracelet.