Got quite a few....but the funniest (well for me anyway) was when I was getting followed by a newish Punto on the A580 heading into Manchester.
It was wet and we were going round a big right hander, with a slip road coming down onto the main carriageway just as the road starts to straighten, felt the esp kick in a bit as the front end's line tighten ever so slightly (was very slight btw, no excessive speed involved) and I saw this flash of blue in my rearview mirror, yep the Punto was changing direction - BIG TIME! Looked back in the rearview when I'd straightened up thinking that the idiot was heading back up the slip road the wrong way only to see it hit the wall head on, he'd obviously lost it on the bend.
Was heading back an hour or so later and saw the Punto getting winched onto a recovery truck, all the airbags were out and it was a proper mess
Rang the Police when I got back to the office and was told all the occupants were completely ok. Then I could have a really good laugh about it