If you are the holder of bearer bonds, you may find that there are only a few banking agents still around that will cash your coupons, and you may have to send them to a processing center to get paid. (investopedia.com)
There are U.S. - issued bearer bonds still in circulation because of their long lifespan — up to 50 years — but, according to an article that appeared in The New York Times on February 13, 2006, by 2013 most of these bonds will have become extinct. (investopedia.com)
I'm aware of the risks to things like bearer bonds, but I think in my case the issue is moot. (money.stackexchange.com)