Well, I'd definitely draw 'inappropriate things' if I was forced to do it.
edit: apologies, that's completely incorrect.
While it is compulsory, you are incredibly unlikely to be fined for not registering. The AEC typically sends a reminder every few years if they have information on your residential address from another government agency.
Once you are enrolled though, if you fail to vote at an election you will be asked to explain your absence and, without a satisfactory excuse, fined.
It looks like the AEC now has the power to automatically enrol you too.
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It is compulsory by law for all eligible Australian citizens to enrol and vote in federal elections, by-elections and referendums.
You are eligible to enrol if you:
* are an Australian citizen, or eligible British subject,
* aged 18 years and over, and
* have lived at your address for at least one month.I would also draw penii if voting was compulsory.