Cheapest I could find for powerboards with individual switches for each outlet. They have surge and overload protection if that makes you happy (aren't these things pretty much pointless?).
Further discounts apply for bulk orders:
2 Pack $33.90 = $16.95 each (shipped, less for pickup Dandenong VIC)
4 Pack $59.80 = $14.95 each (shipped, less for pickup Dandenong VIC)
6 Pack $85.70 = $14.28 each (shipped, less for pickup Dandenong VIC)
10 Pack $137.50 = $13.75 each (shipped, less for pickup Dandenong VIC)
No Usb