Synth Sort -> metaCompress v0.1a

8-bit test
11010010 :: +4
1101 :: +3 // 0010 :: (+1)
[11] :: +2 // 01 :: (+1) \\ [00] :: +0 // 10 :: (+1)
0 :: +0 // 1 :: (+1) // 1 :: +1 // 0 :: (+0)

output +4+3+2+0+0+1

binary out 0100 011 10 00 0 1

>>18
Taking a 4GB file there is very high chance some form of compression will compress it to 4GB-1byte.
There are 2^2^32 different 4GB files. There are 2^(2^32 - 1) different 4GB-1byte files. Therefore no more than half of 4GB files can be compressed by 1 byte (and even in that case you have to do something with all 4GB-1byte files). Note that the file length is actually irrelevant.