print "E-mail address:";
my $email = <>;
chomp $email;
until ($email =~ m/^[a-z0-9]@[a-z0-9]$/ && $email ne "" && $email =~ m/^[a-z0-9]@[a-z0-9].*$/)              # While input is wrong...
        {
        print "Uppps, sorry man, but it doesnt look like E-mail address :/";
        print "Wanna try again? ";     # Ask again
        $email = <STDIN>;             # Get input again
        chop $email;                      # Chop off newline again
        }