Driving a motorcycle unsafely in mixed traffic without a license, registration, insurance, experience, or the ability to read the road signs. Saw two doing unsafe stuff on my way to work today. Not sure specifically where they are from, I didn't stop to ask. I can infer non-compliance from the license plate types with decent accuracy though. Generally plates that say NN (foreign resident), NG (foreign organization), or LD (local enterprise) are compliant and others are not. There are a couple of exceptions beyond that, but they are quite rare.

One nearly got hit by a bus as they cut across the road at an intersection. The other was just being pushy but didn't outright do anything that would get them killed -- not really out of the ordinary, just 'somewhat unsafe'.