Net-SMS is a simple java based desktop application to send sms through free and paid service providers, This application is quite easy to use and supports rich address book features.
Note: In order to send sms with this application you will need to have a way2sms.com account, for which you can sign up for free and then you can send free sms to any number with this free windows application for windows.
Following are some key features of this application
1. Send free SMS from desktop through Way2SMS.
2. SMPP interface to connect and send SMS through SMSC.
3. Rich address book to maintain contacts.
4. Groups of contacts in address book.
5. Username and password remember option.
6. Search engine to locate service provider for any number in INDIA
7. Import contacts from Google, Yahoo, Outlook Express address-book
But you can send SMS for free maximum 140 character at a time.