Yes, CrashPlan can backup NAS devices. However, there are a few things to keep in mind. First, CrashPlan can only backup files that are stored on the NAS device. It cannot backup files that are stored on your computer. Second, CrashPlan can only backup files that are accessible via the network. If the files you want to backup are not accessible via the network, you will need to copy them to the NAS device first.