Running on Empty

Last week, on my way to a meeting, I put about $30 worth of gas in my tank. After returning from the meeting, I parked the car and didn't drive it again until last night when, once again, I had a meeting to attend. On my way to the meeting, I looked at the gas gauge and was shocked to see the needle well into the red. My first thought: something is wrong with the gauge. It's reading was incorrect. Second possibility: a leak. When I stopped at the gas station to fill up I realized that the tank was empty and there didn't seem to be any leak. Solution? Someone likely siphoned my gas while I was out of town last weekend. Infuriating! I'm going to Advanced Auto Parts today to see about getting a new gas cap--one with a lock. Argh.