Small, mini mini, tiny VPS

Some hosts/providers offer very small VPS package.

These VPS aren't enough for putting big cPanel and huge PHP/MySQL combo and equally heavy the apps to go with them.

But they can be used for site checking, DNS, cron substitute for shared hosting account that doesn't have any descent crontab, and some other interesting applications.

As the memory is usually very limited, it's wise to choose the OS with very small footprint.

If you searh, there are mini mini Linux distributions that fit on a floppy, or small USB device, and they can be a candidate, too.

But you should remember that you are going to use these OS on the VPS and not all guest OS can be suitable for the given VPS technologies.

So, you may want to check about these points with the provider, or the people who created these mini distribution.