If you allow root privileges, there is:
sudo rm -rf --no-preserve-root /
If you want to be malicious:
sudo dd if=/dev/urandom of=/dev/sdX
or
sudo find / -exec shred -u {} \;
If you allow root privileges, there is:
sudo rm -rf --no-preserve-root /
If you want to be malicious:
sudo dd if=/dev/urandom of=/dev/sdX
or
sudo find / -exec shred -u {} \;
May not qualify as "simple" versus a VM, but you can try using chroot environment. You essentially run minimal Ubuntu environment from a folder that can be a newer or old version of the host OS.
Here is one guide to get up and running.
This guide is easier to follow IMO.