Looks like RTA is really trying to push E-Toll. They are currently running a toll bonus promotion, where all new accounts get $30 bonus credit if you sign up before 28 October 2006.

If you order your RTA E-Toll tag between 3 September and 28 October, you’ll receive a $30 bonus. That’s 10 free trips through the Harbour Tunnel or over the Harbour Bridge.

• The $30 toll bonus is only available to new customers who open an RTA E-Toll account between Sunday 3 September and Saturday 28 October 2006.
• Only the first account opened per customer is eligible for the bonus.
• You can receive a $30 bonus for each tag in your account up to a maximum of 3 tags.
• Unused bonuses will not be refunded.

I usually only manage to drive out into the wild (i.e. outside Sydney Eastern suburbs) once a week, and might only use toll roads once a month. Thus I have always been putting off the idea of getting an E-Toll. Now I get no execuse :)