expired Kit Kat Gold 170g Block for $3 (U.P. $3.90) at Giant [Paya Lebar Square]
Apparently "limited edition" in Australia but they're now appearing on Singaporean shelves too! It's been as low as AU $2.25 in Australian supermarkets.
Anyhow you can't seem to find this online anywhere in Singapore (besides third party sources), but you can get a block for $3 instead of $3.90.
via Singapore Atrium Sale