Tired of people trying to get your attention? Need a little peace from incessant peeping?
Cruise into your User Settings -> General Options and tell the world to bugger off by setting yourself to Unmentionable and stop receiving notices of when people @Mention you.
For the time period you have this feature Enabled new attempts to Mention you will not be delivered. Turning it back on will not bring back any @Mentions that were suppressed during your "quiet" period, they'll stay gone. There is no visible indicator to people trying to @Mention you that the message isn't going through (Looks like a normal mention, just doesn't go anywhere).
(This does not change how quoting a user behaves, only mentioning)