ppmd 10.1-4 (i386 binary) in ubuntu precise

 ppmd predicts the probability of a given character based on the
 characters that immediately precede it (as all PPM compressors,
 see also Markov Chains and Context Modeling). This archiver
 should be better than zip, gzip, bzip2, zzip, szip and ppmz(2)
 at compressing files.