p7zip's LZMA can be parallelized, and it has plenty of tuning knobs.
There are other LZMA implementations, too. You want Markoff chains for
really repetitive data.<p>The big disadvantage is that p7zip doesn't really <i>do</i> unix pipes,
courtesy of its dosbox heritage.<p>Shameless self-promotion, though weblogs are different than database dumps:<p><a href="http://news.ycombinator.com/item?id=1060821" rel="nofollow">http://news.ycombinator.com/item?id=1060821</a>