Makeuseof has another useful roundup, this time of websites that let you send free SMS messages to a cell phone from your pc.
http://www.makeuseof.com/tag/10-sites-to-send-free-text-messages-to-cell-phones-sms/
[ You are not allowed to view attachments ]
(http://www.makeuseof.com/tag/10-sites-to-send-free-text-messages-to-cell-phones-sms/)