cancelled stamps
 

I remember once when I went to visit my aunt when I was little, I helped her rip cancelled stamps off envelopes to donate them to a charity. I'm currently going through everything I've collected from my 5 years of university, and there's a LOT of old mail in there (my mom went overboard)...

Does anyone know of an organization that takes donations of cancelled stamps?? It's something really small, but if it can help people somehow, I'd really love to do it...