OK so I've blocked a bunch of file type requests by putting this in my conf
[code]
location ~* \.(exe|com|dll|conf|log|htr|cer|cdx|bat|cmd|mdb|php|asp|aspx|zip|rar|cfg|dbf|udl|old|bak)$ {
break;
return 444;
}
[/code]

But what is the syntax if I want to block any URL requests with certain characters, such as @ and ! etc etc.??

Thanks very much.