Just added a new article on building a time-stamp server which remembers the last served time-stamp (USB interfaced). This project is aimed primarily at secure designs which require a method of determining if the host's log files have been tampered with by comparing the last served time-stamp against the information stored by the device.

It also shows how to interface a DS1302 real-time clock chip over USB with a super-cap backup:

http://www.waitingforfriday.com/index.p ... ta-Logging