Even if you haven’t heard about BusyBox, you may have used it. It runs in every ESXi, which doesn’t have a full OS as console like classic ESX. Still, you need an easy way to interact the hypervisor directly. So the ESXi includes a tiny console that uses BusyBox (reduced version) due to its small size.
The BusyBox has been ported to Windows as well. You can download the 600+K executable here. It’s really a simple exe file and you can place it anywhere.