The timeframe: Sometime before DOS was gone, when IPX was still the standard for networked gaming.
The event: A LAN party combined with a normal-type party at the Marshmallow Peanut Circus, a geek house in which I once lived in Santa Cruz, California.
The anecdote: There are approximately equal numbers of DOS users and Windows 95 users. Late at night as we are playing Duke Nukem 3D, all of the Windows users are booted out of their DOS game (which promptly crashes) and greeted by a dialog box:
Windows has updated your clock as a result of Daylight Saving Time.
Much mad howling ensues. Various DOS users can be seen looking smug.