Floating Glass Shelf down to $4 at Kmart Castle Hill. Seen in the bathroom storage section (last aisle before photo books), at least 20 units left in stock.
Unsure if it's in all stores, model no longer sold online. Looks like they're clearing this stock in favour of the new marble and industrial looking shelves.
I saw these at North Rocks yesterday, in the area between storage containers and sports toys. I seem to remember they were $5, but didn't really take great notice. Maybe a price match is in order?
Anyway, they have stainless steel looking trim, but the wall bracket was not stainless (maybe some kind of white metal die casting).