"Me too".

The above two sensible gents are quite right in observing the rider's attitude.
A bit of Zen goes a long way. Call it humility if you like. We are not the lords of the road, and we've made our share of mistakes.
So rather than "punish" careless drivers, be thankful you're still upright. By all means give them a beep to let them know they missed you this time, but not a long, aggressive blast.
As we all know by now, it's all about reading the traffic. We remain in high alert, expecting there will be drivers who don't look or are on their phones.
Stroppy makes a good point- if heavy traffic spooks you, avoid it or change your attitude and/or technique.
Alan makes a good point- pedestrians or skateboarders are another hazard entirely. At least they're softer than us on our bikes.
