Big Beat Club, 998 San Antonio Road, Palo Alto, CA

Owner Yvonne Modica, quite an interesting figure in her own right, had been a successful restaurant and night club entrepreneur in the Bay Area since the 1950's.
According to Yvonne Modica's obituary, one of the innovations of The Big Beat was a "breakfast show" from 2 to 6 am on Saturday and Sunday mornings, where no liquor was served. Apparently musicians would finish their other gigs, and come to jam and hang out until the early hours. Breakfast shows were a regular feature of Jazz clubs in San Francisco and later there were a number of rock or soul breakfast shows around the Bay Area, including at Winchester Cathedral in Redwood City, Frenchy's in Hayward or Modica's other club, The Trip in San Mateo, which opened later in 1966.

While the well-kept building is now vacant, it still looks very much like the 1960s pizza parlor and dance club where the Dead played an acid test. The location of the club, in a then deserted industrial district near Highway 101.(1)
Although The Big Beat continued to exist, it dropped completely off the psychedelic radar. The club was open at least until Spring 1968. Charlie Musselwhite performed here on March 24, 1968.

12/18/65 Grateful Dead
Seven days after they first performed as the Grateful Dead.
Ironically enough, The Big Beat's lasting fame came the weekend before it opened, when Ken Kesey's crew rented the place for a party, and the Grateful Dead played at The Acid Test.(1)
Held in a metal warehouse west of the railroad tracks, the event at the "Big Beat Club" was one of Kesey's Acid Tests.
"There were lots of people with their faces painted and a real carnivalesque feeling," remembers Nelson, now a San Francisco songwriter. "It was like a burgeoning rave scene, a million raves thrown into one."
"The Big Beat came out of nowhere. This is where everybody played, the next step from the coffeehouses," Williams says.
But before the Pranksters got on their now-famous bus, they treated the Peninsula to public acid tests. Spencer, a Perry Lane resident, was at the first one, in a warehouse down by the mudflats off Bayshore Road. He said it was the Grateful Dead's first big public performance.
"So was Neal Cassidy, among other soon to be infamous folks (the Dead, but they might have been the Warlocks at that point, and all the Pranksters). He and his girl-friend were having an argument at one point...very entertaining for the rest of us!"(2)
Interestingly, someone who attended recalls two stages on opposite sides of the building (a common arrangement, making it easy to switch over to a new band) and an all-girl band who alternated with the Dead.

1.)^Rock Prosopography 101, 2009-08-14, http://rockprosopography101.blogspot.com/2009/08/december-18-1965-big-beat-palo-alto.html
2.)^ Bell, Margaret, 2009-09-01, http://www.paloaltoonline.com/square/index.php?i=3&t=551#add_comments