Tigerdog may be referring to smspup.com.au. Yes you do recieve junk mail, but all you have to do is open the letter and click on 'view' and you get a free sms. It's a pretty good service, you get five free sms' simply by joining up, and a good chance to get more, and it's pretty quick to send an sms. I recommend it. Also, you can 'opt out' at any time.