SISAL is an efficient functional programming language for numerical computation on both serial and parallel computers. It has advantages of safety and clarity over conventional programming languages, and it parallelizes without programmer intervention on certain machines. (Unfortunately, not Linux for now!) Try it, you will like it! Click here to download the compiler and documentation. (About 1.5 MB gzipped.) The Sisal project resided for a long time at Lawrence Livermore National Laboratory, but was recently canceled there. Source code and documentation may or may not be available via anonymous ftp at sisal.llnl.gov as you read this. I have tried to collect all relevant source code and documentation into the above download. The complete LLNL Sisal tree is now reproduced in tarred gzip format here.