we are developing an SMS website and we are planing to buy GSM modem and link it to pc and use our SIM card to send SMS .
requirements summary here
2) Hosted GSM modem.
3) Send to Mobile button among searches on the site , mp3 , pics , .. (this will basically involve the sms app you will develop to send pictures links from our site by sms )
4)share this button for webmasters , giving them a code to host on theri sites share via SMS
5) Text Me button for social networks . code contains their Cell # .
6)[url removed, login to view] straightforward SMS app with option to charge , limit spam , block ips , ...
if you got any question on the above let me know