Good candidates include Python (do you agree on that?): It's said to be simple and fast to learn as well as free:
- https://www.python.org/
- http://www.astro.up.pt/~sousasag/Python_For_Astronomers/Python_qr.pdf (cheat sheet)
- https://perso.limsi.fr/pointal/_media/python:cours:mementopython3-english.pdf (cheat sheet)
- http://lifehacker.com/keep-this-python-cheat-sheet-on-hand-when-learning-to-c-1655521825 (cheat sheet)
- http://www.tecmint.com/the-truth-of-python-and-perl-features-pros-and-cons-discussed/ (Perl vs Python)