Yep, icc is free to download.

http://software.intel.com/en-us/articles/non-commercial-software-download/


# Intel C++ Compiler (ICC)
# ------------------------------------------------------------------------------
# http://software.intel.com/sites/products/documentation/hpc/compilerpro/en-us/cpp/mac/man/icc.txt
# http://web.eecs.utk.edu/~lucio/pet/compilerguides/intel-compiler-guide.htm
# ICC - From +10% (PHP) to +150% (MySQL)
# - http://www.mysqlperformanceblog.com/files/presentations/LinuxWorld2005-Intel.pdf
# - http://blog.mudy.info/2009/02/speedup-mysql-and-webserver-with-intel-compiler-and-tcmalloc/
# - http://mysqlha.blogspot.com/2009/01/double-sysbench-throughput-with_18.html
# C : icc -fast
# C++ : icpc -fast
# Fortran : ifort -fast
# Documentation : /home/intel/l_ccompxe_intel64_2011.8.273/Documentation/en_US/documentation_c.htm
# Videos : www.intel.com/software/products
# Support account : https://registrationcenter.intel.com/RegCenter/registerexpress.aspx?clientsn=YOURKEY
#sudo cp -fr /www/l_ccompxe_intel64_2011.8.273.tgz /usr/local/src/l_ccompxe_intel64_2011.8.273.tgz
# cd /usr/local/src
# sudo rm -fr l_ccompxe_intel64_2011.8.273
# sudo wget -O l_ccompxe_intel64_2011.8.273.tgz "http://www.denistruffaut.com/downloads/l_ccompxe_intel64_2011.8.273.tgz"
# sudo tar -xvzf l_ccompxe_intel64_2011.8.273.tgz
# sudo rm -fr l_ccompxe_intel64_2011.8.273.tgz
# cd l_ccompxe_intel64_2011.8.273
# sudo ./install.sh && cd /usr/local/src
# sudo rm -fr l_ccompxe_intel64_2011.8.273