From its docs:

Sometimes it's necessary to protect some certain data against plain reading or you intend to send information through the Internet. Another reason might be to assure users cannot modify their previously entered data in a follow-up step of a long Web transaction where you don't want to deal with server-side session data. The goal of Crypt::Lite was to have a pretty simple way to encrypt and decrypt data without the need to install and compile huge packages with lots of dependencies.

A few years ago I saw a code that converted everything to 1s and 0s and it was easy to encode and decode from that but I can't find it.

Bit-wise not (~) applied to a string does exactly that very efficiently:

$s = 'The quick brown fox jumps over the lazy dog';;
print unpack 'C*', $s;;
84 104 101 32 113 117 105 99 107 32 98 114 111 119 110 32 102 111 120 
+32 106 117 109 112 115 32 111 118 101 114 32 116 104 101 32 108 97 12
+2 121 32 100 111 103

$t = ~$s;;
print unpack 'C*', $t;;
171 151 154 223 142 138 150 156 148 223 157 141 144 136 145 223 153 14
+4 135 223 149 138 146 143 140 223 144 137 154 141 223 139 151 154 223
+ 147 158 133 134 223 155 144 152


$u = ~$t;;
print unpack 'C*', $u;;
84 104 101 32 113 117 105 99 107 32 98 114 111 119 110 32 102 111 120 
+32 106 117 109 112 115 32 111 118 101 114 32 116 104 101 32 108 97 12
+2 121 32 100 111 103

print $u;;
The quick brown fox jumps over the lazy dog
[download]

tr/a-zA-Z/n-za-mN-ZA-M/;
[download]

If it is a combination of predefined values consisting of both numeric and string values nicely stashed up in a structure, I'd suggest using a combination of a serializer like Storable and a simple binary-text converter like builtin pack.

use Storable qw( nfreeze thaw );
my $game_data = {
    score    => 1425,
    hits     => 3,
    name     => "Supernova",
    accuracy => 0.34,
    :
    :
    };

my $enc = unpack "H*" => nfreeze ({ game_data => $game_data });
# $enc now contains something like
# 05080300000001040300000004088300000004686974730a0953757065726e6f7661
+000000046e616d6509000005910000000573636f72650a04302e33340000000861636
+375726163790000000967616d655f64617461
[download]

On the receiving side, other way round ...

use Storable qw( nfreeze thaw );
my $game_data = thaw (pack "H*" => $enc)->{game_data};
[download]

It is up to you to decide how <c>$enc gets transported between the games.

Encryption is encryption, full blown or not. If you want encryption then use what CountZero recommended.

If you want something a little easier to work with (and for humans to encode/decode) use MIME::Base64.