This concept was initialized by two Polish guys, Dariusz Patecki and Marcin Najdyhor. They started with a Polish version, http://www.wirtualnycmentarz.pl/ and now they have an international/English version, http://www.virtualgrave.eu/.
Is this for fun? I’m not sure but you actually can buy a virtual grave at 2 EUR or if you prefer a custom made grave for about 120 EUR!!
On top of that you can purchase candles and flowers!!