You can get in a lot of trouble for taking a shot or two before getting behind the wheel. This woman was caught doing a some heroin behind the wheel while steering with her knees. She must have already been under the influence, as she was next to and keeping pace with a police cruiser when she shot up.
Needless to say, she and her passenger were promptly arrested.
What's the stupidest thing you've seen someone do while driving?
[via Dayton Daily News]