I have just tried Virtual Sandbox from Fortres Grand Corporation. You can download it from the following URL:
http://www.fortresgrand.com/products/free/vsb_free.htm
I found the program to be annoying because it alerts you for unknown applications like Comodo’s D+. While D+ gives you a choice between allowing, blocking, or treating as an installer/updater, trusted application, isolated application, or limited application, Virtual Sandbox gives you a choice between terminating, running normally, or running in a sandbox. What makes Virtual Sandbox worse than D+ is that with the former, it takes longer for the computer to boot up. With CIS, the computer boots up faster. In addition, D+ tells you exactly what is about to happen, e.g., a registry modification, file modification, etc. Thus, D+ is better than Virtual Sandbox.