"If a virtual transaction has real world implications — if it can be attributed a monetary value — it attracts the attention of the Tax Office. Sites such as slexchange.com set rates for swapping Second Life's Linden dollars for 'real' money. 'The real world value of a transaction may form part of your taxable income, even if it is in Linden dollars,' the ATO spokeswoman says. 'In addition, there may be GST (goods and services tax) to consider.' In other words, if you are turning over the equivalent of more than $50,000 selling virtual jewelery to Second Life avatars, you must get an ABN (Australian Business Number) and register for GST."