1. A mobile security system, comprising: a runtime memory; a preboot memory for storing at least a portion of an operating system, wherein the preboot memory is configured to copy and load the at least a portion of the operating system into the runtime memory when the mobile security system is rebooted; a connection mechanism for connecting to a data port of a mobile device and for communicating with the mobile device, the mobile device having a mobile device processor; a network connection module for receiving content intended for the mobile device; security policies defining unacceptable malicious content; security engines for examining the content received by the network connection module for the unacceptable malicious content as defined by the security policies, the security engines operating at different layers of the OSI stack; a mobile security system processor executing the security engines in the runtime memory using the operating system, the mobile security system processor being different than the mobile device processor; and a backup module capable of storing at least a portion of the boot sector of the mobile device should the boot sector of the mobile device become compromised.