I'm a crazy girl that loves to travel and I'm always happy to learn new people Many Couchsurfer ask me usually what they could bring for me. To be honest, bevor you break your head and waste your time while looking for "present" I would suggest you rather to donate those 10€ to a foundation in Madagascar where I was working as a volunteer. I think it's better then caring heavy bottles and with 10€ you can make a miracle for those children.