liblzma2 4.999.9beta+20100810-1 (amd64 binary) in ubuntu natty

 XZ is the successor to the Lempel-Ziv/Markov-chain Algorithm
 compression format, which provides memory-hungry but powerful
 compression (often better than bzip2) and fast, easy decompression.
 .
 The native format of liblzma is XZ; it also supports raw (headerless)
 streams and the older LZMA format used by lzma. (For 7-Zip's related
 format, use the p7zip package instead.)