I had lost my flash drive on countless time. I usually was able to keep my pen drive a month or two and sometimes I didn't even realize when I was losing them. This time I would like to make sure that I won't loose any of my new pen drive anymore. I came out with a very simple solution.
The simplest way on how to prevent flash pen drive from getting lost is to attach something big to your flash drive. In my case I used fluffy animal love shape that I just bought recently. Simple yet effective.
Update on 18 October 2013: The pen drive still hasn't lost ;)