I have a large collection of mostly unused postcards, accumulated through travels around the world. While in Japan (fantastic postal system there) I enjoyed sending cards to friends and family inside and outside Japan. Postage was cheap, and delivery was quick. Once back in Australia, I found it hard to find anyone who wanted to receive postcards, or exchange them. Then I found Postcrossing.com - a website that lets you send and receive postcards from random people around the world.
I love the glimpses of other peoples lives that I get. I like seeing what cards they send. I love getting mail that isn't flyers or bills.
I do regret the decision to scan and post them on the blog sometimes- particularly on the days I receive 10 postcards!