I have no problem giving friends a ride, but I wouldn't mind getting paid for my troubles. That's where the Japanese Replica Taxi Meter can come in.
Running a taxi service without a franchise is probably illegal, but being an outlaw has always been more fun. Plop this thing on your dashboard and begin ferrying passengers around. If anyone asks why your meter is in Japanese, tell them it's actually Chinese, because the cab company is from Chinatown. All those strange Asian alphabets look the same anyway.
Since you just plop it on the dashboard, we doubt the Japanese Replica Taxi Meter can actually measure how far you've travelled. Based on the pictures, though, the number does change, so maybe that meter runs with time. Hopefully, it can be calibrated to mirror typical rate per travel times for your city. If it can't, then all the better, since the Yen's conversion rate will definitely fall in your favor.
For added effect, make sure to only turn it on once the passenger boards. In case charging drunk people $2,000 for ferrying them a block leaves you swimming in guilt, tell them you offer a 1,000 percent discount (adjust the markdown as necessary). The Japanese Replica Taxi Meter is available for ¥3,200.00 (about $35).