Maybe I have just got old, but I cant imagine spending 10 hours or so overnight in SF with nowhere to go. This is not a 24/7 city. Depending on what terminal you come into this could be very sad.
But, I suppose, if you feel you must, there is a "Prayer Room" right outside the Bart Entrance in the International area. As long as you are quiet, you can hang out there.
There is a corridor between T1 and the International terminal, past the check in counters, past the museum exhibits, but before the International Terminal. I'd hang out there...
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D'oh, that closes too...you are screwed...
Berman Reflection Room
The Berman Reflection Room provides a center for quiet self-reflection and meditation.
International Terminal, Pre-Security
International Terminal, Main Hall
Hours of Operation: Daily, 7:00 a.m. to 11:00 p.m
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Ha ha, you can sleep in the Yoga Room
Yoga Room
Space devoted to relaxation, self-reflection and practicing yoga. There is no charge to use the facility.
Terminal 3, Post-Security
Boarding Area E near Gate 69
Hours of Operation: Daily, 24 hours
http://www.flysfo.com/services-ameni...enger-services