Googles Compute Engine VMs which are configured preemptible are massively cheaper than regular VMs, typically a fourth or even a fifth of the price of a regular machine. It seems quite lucrative for everything which is not mission critical.
However, it can be quite annoying when all state gets lost. Luckily Google does not just turn off the machine but sends an ACPI G2 Soft-Off signal. With Debian 9 (stretch) the ACPI daemon is processing the ACPI signals (acpid) and by default shuts down the machine. This post shows how to use hibernate instead.
Note: Since Google might start the machine on a different (virtual) hardware resuming the machine might not succeed, or even worse, lead to adverse effects. In practice, it seems to work quite well for me 🙂