I have a database which contain many name with combination of those characters. Once i will reload them, they will become public web url.
So that visitor if open this url (its valid??): http://www.example.com/&*Ö::
It will land to a unique page. But do you really allow those characters? Or filter them. Or there is no rule really, anything is allowed.
(I can already see, http://webmasters.stackexchange.com/questions/23964/how-to-allow-nonsense-characters-as-web-url-for-example-and-more
, skiped my special characters and only took "and more". Is that the standard? I mean you can delete the main character?)