Keep it...my grandfather was a million-miler in the jet age on Pan Am, etc...and had been all around the world. I had a few small bags, sorted by continent, with coins from probably over a hundred countries.

My parents sold their house (the one I had grown up in) and many of our possessions, and brought the bags of coins to the bank, and traded them in for something like $100, most of it was considered worthless since the currencies were out of circulation. It still makes me LIVID to think about it, as that was one of my favorite possessions, and I had been adding to it with spare change as I returned from my own travels.

Keep it in the family, give it to a kid, grandkid, younger cousin, whatever. It's a great conversation starter and had 10-year-old me absolutely riveted. I loved that stuff! Maps, coins, geography, aviation, lots of fun.