Adapt browser time based on tor's notion of clock skew...
TorButton / Tor Browser Bundle user with inaccurate system time (e.g. offset >5minutes or even hours) might be fingerprintable based on there system time. What do you think about a feature in TorBrowser that would warn an user with inaccurate system time and suggest NTP if the system time is off by more than a certain (configurable) amount of time?