IF YOU happen to be a night watchman or an ER doc working the graveyard shift, late-night dining is just part of what you do. Getting off work at 5am and going out for a burger and a beer isn't so out of the ordinary. But for the rest of us with circadian rhythms tuned into the 9-to-5 frequency, there's something strange and strangely exciting about sitting down to eat in the middle of the night.

Depending on your mental state and that of those around you, the experience can range from satisfying to surreal. Once I was chowing down at a Denny's in San Diego early one morning when someone hurled a brick through the window. The packed house of drunks, surly Vietnam vets, college students and coffee-drinking skinheads barely took their eyes off their Grand Slam Breakfasts and grilled cheese sandwiches.

Because late-night meals take place between dinner and breakfast, there are no rules. Technically, in the three-square-meals-a-day order of things, these late-night meals aren't supposed to exist. You're eating off the books because you're supposed to be asleep. As a result, there's something liberating, almost naughty, about ordering a chocolate milkshake and a Denver omelette in the dark hours before dawn.

Slide into a booth at one Silicon Valley's night owl diners in the wee hours and prepare for a heaping side order of humanity in various states of hunger, intoxication, insomnia or paranoia. Your dining mates will likely be a motley mix, loaded party people recently turned out by closing bars in need of french fries to mop up the alcohol sloshing around their bellies, or a clutch of goth chicks plotting their nocturnal ramblings. If it's a quieter weeknight, you might find some well-scrubbed students sharing a table as they cram for a midterm exam.

Or maybe there's a table occupied by a solemn couple who just stare at their club sandwiches and fried shrimp, not talking to each other or anything. What's their story? Maybe they just pulled into town after an 18-hour drive from Wyoming in which they argued the whole time. Or perhaps they're fugitives who've been driving all night in hopes of evading the law! Who knows? Order another slice of cherry pie and an order of chili fries and wait to see what happens next.

Bay 101 (Sutter's Broiler) 1801 Bering Dr, San Jose. 408.451.8888. Open 6am-1:45am. Cardinal Coffee Shop and Lounge 3197 Meridian Ave, San Jose. 408.269.7891. Open 24 hours daily. Carrows Various locations including: 910 Saratoga Ave, San Jose. 408.248.1238. 1696 Tully Rd, San Jose. 408.238.3000. Open 24 hours daily. Denny's Various locations including: 4256 El Camino Real, Palo Alto. 650.493.3082. 311 S. Mathilda Ave, Sunnyvale. 408.245.3715. 3399 Bowers Ave, Santa Clara. 408.727.6330. Open 24 hours daily. Duke of Edinburgh 10801 N. Wolfe Rd, Cupertino, 408.446.3853. Open 11:30am-midnight daily. Happy Donuts 3916 El Camino Real, Palo Alto. 650.843.0658. Open 24 hours daily. La Victoria Taqueria 140 E. San Carlos St, San Jose. 408.298.5335. Open 7am-midnight daily. Mini Gourmet 599 S. Bascom Ave, San Jose. 408.275.8973. Open 24 hours daily. Oasis Beer Garden 241 El Camino Real, Menlo Park. 650.326.8896. Open 11am-1am daily. Original Joe's 301 S. First St, San Jose. 408.292.7030. Open 11am-1am daily. Pizza My Heart 117 E San Carlos St, San Jose. 408.279.0555. Open 11am-11pm Mon-Thu and 11am-midnight Fri-Sat. Spoons 25 S. Fair Oaks Ave, Sunnyvale. 408.720.0136. Open 11am-11pm Sun-Thu and 11am-midnight Fri-Sat. TGI Friday's 10343 N. Wolfe Rd, Cupertino. 408.257.2050. Open 11am-midnight Mon-Wed and 11am-1am Thu-Sun. Top Caf&ecute; 1075 S. De Anza Blvd, Cupertino. 408.996.7797. Open 8am-3pm daily.

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