I wasn't aware of optimized versions of zlib, the free patent-unencumbered compression library, until today. I ran across Juho Snellman's comparison benchmarks of vanilla zlib, CloudFlare zlib, Intel zlib, and zlib-ng. The upshot is that CloudFlare's optimizations seem to be the best performing. And its decompression times were 75% of the vanilla version, while Intel and zlib-ng ran at 98% and 99% respectively. This would be a clear win for read-intensive workflows, such as some bioinformatics workflows.
Read more about how CloudFlare was contacted by the Institute of Cancer Research in London to help improve zlib at this blog post by Vlad Krasnov. Intel has an overview of zlib in its Intel Performance Primitives (IPP) product. And this is zlib-ng's GitHub repo.