It is at http://tukaani.org/lzma/. There are a number of advantages compared to Gzip and Bzip2:
* The average compression ratio of LZMA is about 30% better than that of gzip, and 15% better than that of bzip2.
* While the decompression speed is slightly slower than gzip, it is two to four times faster than Bzip2.
* In fast mode, compresses faster than bzip2 with a comparable compression ratio. However, achieving the best compression ratio is slower than bzip2, but doesn't affect decompression speed.
* A very similar command line interface that is like what gzip and bzip2 have.
* Tar-1.20 and higher can unconpress LZMA-commpresed tarballs with the --lzma switch.
* And it's licenced under both the GNU GPL and LGPL.
No wonder why most of the newer GNU packages come in lzma and gzip (not Bzip2). And there may be a few lzma-only tarballs along the road, like the Texlive source. I think this package should be in LFS.