What are some alternatives?
When comparing Boxes and VirtualBox, you can also consider the following products
Parallels - Parallels Desktop is a virtualization software for Mac users to run Windows and Linux apps on OS X.
Workstation Player - Download VMware Workstation Player for free today to run a single virtual machine on a Windows or Linux PC. Organizations use Workstation Player to deliver managed corporate desktops, while students and educators use it for learning and training.
VMware Fusion - Simple and powerful virtual machine for Mac. Mac virtualization software. Learn more about VMware Fusion and try it free today.
QEMU - QEMU (short for "Quick EMUlator") is a free and open-source hosted hypervisor that...
VMware Workstation - VMware Workstation is a multiple operating system handler to easily evaluate the any other type of new operating systems.
Proxmox - Proxmox is an open-source server virtualization management solution that offers the ability to manage virtual server technology with the Linux OpenVZ and KVM technology.