A USB peripheral device may automatically launch an application residing in its memory after it is connected to a host or after restarting the host if the USB flash drive has already been connected. Alternatively, the USB peripheral device can automatically launch an application residing on the host or on a network, which is accessible by the host. The USB peripheral device has a USB interface and a controller, which is operative to execute instructions for sending and receiving messages through the USB interface. The controller is further operative, when executing the instructions, to send to a host a stream of emulated keystrokes, which emulated keystrokes cause the host to generate and execute a startup script. Embodiments of the invention include a USB peripheral device able to control a host and a method of using a USB peripheral device to control a host.