going on any footballers most popular youtube video and seeing legions of simpletons writing "welcome to *insert team*" just because they were linked with them in the papers.
As a regular cyclist, this blows my mind when I see people do it.
So much less likely to die when you're in a bike line, let alone a separated cycle path.
On this subject: Fellow cyclists who think traffic lights don't apply to them. Do you want to be thought of as an accepted part of normal traffic? THEN FOLLOW THE RULES.