Find out what's open with WhatsOpen
That's where WhatsOpen comes in. Just type in what you're looking for and where you're looking. For example, restaurants in San Francisco or coffee shops near Mountain View. WhatsOpen will bring up a Google Maps mashup with store information, phone numbers, and hours of operation. While WhatsOpen doesn't seem to include holiday hours, the site could come in handy if you're looking for a place to buy groceries in the middle of the night or if you have a sudden urge for coffee at 2am.
WhatsOpen recently launched a public demo that covers California. But you can also sign up for a beta account covering the US, China, and Europe.