Some variations on four themes: substr($s, 0, 1, ""), $s =~ s/.//s;, and use of split and unpack.

$s = (split /./s, $s, 2)[1] err ""; # Needs 'defined-or' patch, or 5.9
+.1
$s = (split /./s, $s, 2)[1]; $s = "" unless defined $s;
$s = length $s ? (split /./s, $s, 2)[1] : "";
$s = join "", map {substr $s, $_, 1} grep {$_} 0 .. length($s)-1;
substr $s, $_, 1, $_ ? substr($s, $_, 1) : "" for 0 .. length($s)-1;
local $a = 0; $s = join "", grep {$a++} split //, $s;
local $" = ""; $s = "@{[(split //, $s)[1 .. length($s)-1]]}
$s =~ s/(?<!.).//sg;
local $a; $s =~ s/.(??{$a++ ? "(?!)" : "(?=)"})//sg;
$s = pack "A*", (unpack "A*", $s)[1 .. length($s)-1];
$s = pack "A*", unpack "xA*", $s if length $s;
$s = pack "A*", unpack "xA@{[length($s)-1]}", $s if length $s;
[download]