USB is used in almost every computing device produced in recent years. In addition to well-known usages like keyboard, mouse, and mass storage, a much wider range of capabilities exist such as Device Firmware Update, USB On-The-Go, debug over USB, and more. What actually happens on the wire? Is there interesting data we can observe or inject into these operations that we can take advantage of? In this talk, we will present an overview of USB and its corresponding attack surface. We will demonstrate different tools and methods that can be used to monitor and abuse USB for malicious purposes.