LUNA: a USB multitool & nMigen library

Some things you can use LUNA for, currently:

Protocol analysis for Low-, Full-, or High- speed USB. LUNA provides both hardware designs and gateware that allow passive USB monitoring. When combined with the ViewSB USB analyzer toolkit, LUNA hardware+gateware can be used as a full-featured USB analyzer.
Creating your own Low-, Full-, High-, or (experimentally) Super- speed USB device. LUNA provides a collection of nMigen gateware that allows you to easily create USB devices in gateware, software, or a combination of the two.
Building USB functionality into a new or existing System-on-a-Chip (SoC). LUNA is capable of generating custom peripherals targeting the common Wishbone bus; allowing it to easily be integrated into SoC designs; and the library provides simple automation for developing simple SoC designs.

Some things you'll be able to use LUNA for in the future:

Man-in-the-middle'ing USB communications. The LUNA toolkit will be able to act as a USB proxy, transparently modifying USB data as it flows between a host and a device.
USB reverse engineering and security research. The LUNA toolkit will serve as an ideal backend for tools like FaceDancer; allowing easy emulation and rapid prototyping of compliant and non-compliant USB devices.