GOG is having a sale and quite a few good games are at a decent price. Sale goes until the 30th. None of the games have DRM, so you can copy paste them to your other computers if you want, and they don't need an internet connection to play.
There's some new games and some older games.
Some examples (all prices in AUD):
* The Witcher 3: Wild Hunt ($17.99, GOTY $23.69)
* Stardew Valley ($13.59)
* XCOM 2 ($22.49)
* Hollow Knight (11.49)
* Wolfenstein: The Two Pack (New Order & The Old Blood) ($22.49)
* Battletech ($15.59, Digital Deluxe $20.09, Mercenary Collection $36.39)
* STAR WARS™: Knights of the Old Republic ($5.39)
* RollerCoaster Tycoon 2: Triple Thrill Pack ($6.19)
* Into the Breach ($11.49)
* Transport Fever 2 ($51.99)