03 Mini won't start -lights out
 

I recently bought a used '03 Mini (not S). This evening I got in, turned they key and the car lost all power... all lights out. I let off the key and slowly it made beep sounds and light flashes on and off. The clock and the trip meter have rest. The keyless lock will not lock or unlock the door. THe inside light flashes on and off. And the car won't start. This feels like a computer crash to me. Can anything be done besides towing it in for service? Like maybe a forced computer reboot? Thanks for any advice.

More info
 

I went back out and found that the car has almost no power now. I figured, dead battery. I hooked up jumper cables and the car again had power. I let it charge for at least 10 min and then tried to crank it. I gave a click / click / click but never turned. I let it sit, charging longer but still it will not start. Watching the belts as the key is turned, it appears the engine is moving a little, but still it's not starting. I gave up and disconnected the jumpers and again the car has almost no power. Almost = with the key in position 1 the air bag light turns on but nothing else. With the key out the milage display is flashing very dimly. I don't have a volt meter so I can't test the charge on the battery. Any other ideas? Otherwise, we're getting a tow.

I'd remove the battery and take it to an autoparts store and have the battery tested and charged

I did that and the battery tested fine. Turns out that, even though the posts/connections looked clean, I cleaned them anyways and it started working again. Thanks for the suggestion!