Installing Erlang on Mac OS X

mkdir erlang
cd erlang/
wget http://www.erlang.org/download/otp_src_R14A.tar.gz
tar xz otp_src_R14A.tar.gz
cd otp_src_R14A
./configure --enable-hipe --enable-smp-support --enable-threads
make
sudo make install
cd ../..
rm -rf erlang

Start the Erlang console:

erl

If you do not have wget, you can install it with Darwin Ports:

sudo port install wget