Mark Mayo has signalled me that I have too many account on stackexchange. And he is right. Some are totally useless. Now I would like to delete those accounts. I have found the following advice:

http://meta.stackoverflow.com/questions/5999/how-can-i-delete-my-account

Alas, this recipe does not work for me. Moreover I cannot post there because ... guess what ... I have no account there! Moreover, what is annoying, there seem to be other questions on the same issue, but they are all routed to the above one.

Can someone please explain me how I can delete some accounts?