It's not like sending an SMS is an expense that's hard to bear but with mobile calling rates being as low as they are at the moment I don't see why we can't find ways to scrip on this too. So if you're worried about your messages taking a hefty toll on your bill here are a few websites that will allow you to send free text messages.
This seems to be the most popular Web to SMS site out there. It's an extremely simple set up and really easy to use. Way2SMS allows you to log into your Gtalk and Yahoo! Messenger accounts and chat right from the same page. It also has an email option wherein you can access your Gmail and Yahoo! accounts and view and send mails, again right from the same site. Way2SMS also had their own email option which is being discontinued now since that didn't seem to fare too well. Users can also upload their contacts from a .CSV file for easier access to the address book for sending texts. The site also saves messages as Sent SMS' and you can also send future texts by inserting a date and time a message should leave the server. It’s very handy for group SMS'.
YouMint is another easy to use WEB to phone SMS site. It allows you to invite users to join the network and even pays you for referrals (hence the name). From the same site you have access to hundreds of online games and YouTube videos that can be shared with your Facebook, MySpace, Orkut or Hi5 accounts. There’s even a huge collection of pre-typed text messages, sorted into categories that you can choose to send to your contacts. The only thing missing was an option for sending group texts and uploading your contact database.