Bury something somewhere for someone else to find

Next time I travel later this year, and also in France, I’m going to leave something for someone, and when I get home map it and leave it on my webpage etc, then whoever finds it can either send it back to me, or send me something new, theres no reason for it, just a way to get a sense of the true size of the world! and the amount of people on it…..I already have my e-mail adress with a lil message scrawled on a cafe wall in Peru, be cool if someone were to find it… Or I find it again!