It looks like the stock broker market is heating up, as we have a new entrant offering both Aus and US trading.
In my search for the cheapest broker for small trades (which led me to the easyequities deal) I also came across Sharesies which appears to be well established in New Zealand and about to expand into Australia.
They are currently offering $15 if you join the waitlist and sign up on launch (launch date not yet known but must be soon as offer expires 30 April).
The $15 must be used for trading before withdrawal. However I expect it should be relatively trivial to make a couple of small trades and cash out the balance. Full T&Cs of the offer.
Beta has been launched. No ASX trading yet, if you want to use your $15 you will need to convert it to NZD or USD first. It appears ASX is coming soon though (don't know why they would launch without it…)
Fee structure has been announced and is not very appealing - easy equities is a much cheaper option.
More details: https://www.sharesies.com.au/pricing
They will also be an authorized rep of Sanlam (same as easyequities, superhero, thinkmarkets). I suspect they will use a custodian model to facilitate low cost/size trades but no details yet.