It’s the season of holiday parties and champagne corks popping. But if you’re partying in the city, don’t drink and drive. Washington Regional Alcohol Program and AT&T are offering free cab rides up to $30 for anyone over 21 from now until January 1, 2012. All you have to do is call 1-800-200-8294 (TAXI) or dial #8294 (TAXI) if you’re an AT&T customer. The holiday SoberRide program offers free rides from 10 PM to 6 AM.