There are countless websites on the Internet that allow you to send free SMS texts to any number in the world. However, most of them are free only for you, while the recipient is charged the usual SMS fee for receiving your text. Also, most of the websites do not allow the recipient to reply. If you want a way for the recipient to reply to your messages, you have three options as of July 2010--Gmail chat, Txt Drop or Peekamo. Luckily, all three of these websites are free for both you and the recipient, and you can receive as many replies as you want.
Visit the Gmail website. Sign up for a new Gmail account by providing personal information, such as your name and address details. Select a user name and password and log on to your Gmail account.
Click the “Settings” link found on the top right corner of the account page.
Click the tab “Labs.”
Scroll down towards the end, and check “Text Messaging (SMS) in Chat.” Gmail text messaging will then be enabled.
Click on “Save Changes.” Your Gmail account will reload. Now you can text people by typing their phone numbers in the search field of the chat box and typing the message in the chat window. Subsequently, you will be able to receive their SMS texts on the same chat window.
Go to Txt Drop’s website (see "Resources" for a link).
Type your e-mail address in the first field.
Type the recipient’s cell phone number in the respective field.
Type the message you want to send in the message box.
Click the button “Send.” Your first message will be sent to the recipient. The recipient will reply to it just like a usual phone-to-phone SMS but you will receive the reply in your e-mail inbox.
Visit Peekamo’s website (see "Resources" for a link). When you open the page, click on “Sign Up for a Free Account.”
Select your country. Also, select your network carrier.
Type in your cell phone number, e-mail ID and password. Click “Next.”
Click “Send SMS.” Now type the recipient’s phone number.
Type in a message and hit “Enter.” Your first message will be sent to the recipient. The recipient will reply to it just like a usual phone-to-phone SMS and you will receive the reply on the same webpage.