Cabbing it is inherently frustrating, what with the nagging suspicion you'd get there faster yourself, and the fear that your driver's curious musk might forever turn you off eating cheesesteaks. Quelling the former, Avego
Conceived in Ireland and launching from its new SF office, Avego's a web/SMS/GPS-powered iPhone app that turns your car into a taxi and your cellie into its meter, setting you up to make 30¢ a mile (and $1 for the first) off those too cheap for cabs and too smart for MUNI. Launch the app out on the road, and Avego will rec potential passengers along your route for you to accept or reject; pick up a fare, and he'll tell you a pin #, which both starts the Paypal transaction and pops up his picture on your phone -- if it doesn't match, you're being duped, so throw scalding coffee in his face. As his destination's approaching, your iPhone'll tell you where to pull over (without altering your route); you'll receive a statement of your earnings (Avego takes a small cut), and be prompted to rate your rider from 1-5 (5 for courteous, safe, and funny-drunk, 1 for drunk and anti-semitic)
To catch a ride, you don't need an iPhone -- just text or call in your destination and Avego'll ping you back when a willing driver's getting close. You can also specify driver criteria, i.e., "over 18", male/female, or "staunch vegetarian".