Free Notation Program from NCH

NCH Software offers a free music score writing and composing software, named  "Crescendo Music Notation Software". It can be dowmloaded on 

http://www.nch.com.au/notation/index.html

for Windows (XP/Vista/ Windows 7 and 8), Mac OS X (10.4 and above), Android (version 2.4.4 or higher) and also for Kindle.