In no particular order. Today...
#1 People who "Queue" adjacent to parked vehicles on the other side of the road in a manner that prevents the passage of oncoming traffic.

Today's example.
(Definitions. Upstream=my side of the road, Downstream=other side of the road)
[Rant]
Me, travelling upstream come to a point where a line of cars are parked on the downstream side of the road. There is a request (No marked bay) bus stop about halfway along the line of parked cars.
A bus, travelling downstream, has stopped to allow passengers to board and alight. this blocks the road. I stop making sure that there is plenty of room for the Bus to clear the parked cars.
Behind me, traffic begins to queue.
Behind me, there are other cars parked on the Downstream side of the road. Upstream drivers queue adjacent to them.....
This means, that when the bus attempts to continue its journey there is no room for it to get through.
The truck that is behind the Bus (And the other traffic that was behind the truck) closely follows the Bus until the Bus cannot proceed further.
If I could move forward, it would be possible for other people behind me to move forward to create space for the Bus to get past the parked car.
Unfortunately the truck behind the bus is now preventing me from doing so.
We are now gridlocked!
Fortunatly, I am in the LC, so I am actually able to break the gridlock by mounting the (Higher than normal) kerb and drive up onto the 30 degree angle grass bank to create enough room for everybody to start moving again.
But really, If I had been in my car (E36 compact), I wouldn't have been able to do this and we would probably all still be there fuming.
As it is, I still might have risked damaging my tyres mounting the kerb (They are road SUV tyres, Not rock crawlers)
And in any case, this situation shouldn't have arisen in the first place if the Rancid, Festering, Chum Buckets behind me hadn't "queued" adjacent to the parked cars.

[/Rant]
#1 People who "Queue" adjacent to parked vehicles on the other side of the road in a manner that prevents the passage of oncoming traffic.

Today's example.
(Definitions. Upstream=my side of the road, Downstream=other side of the road)
[Rant]
Me, travelling upstream come to a point where a line of cars are parked on the downstream side of the road. There is a request (No marked bay) bus stop about halfway along the line of parked cars.
A bus, travelling downstream, has stopped to allow passengers to board and alight. this blocks the road. I stop making sure that there is plenty of room for the Bus to clear the parked cars.
Behind me, traffic begins to queue.
Behind me, there are other cars parked on the Downstream side of the road. Upstream drivers queue adjacent to them.....

This means, that when the bus attempts to continue its journey there is no room for it to get through.
The truck that is behind the Bus (And the other traffic that was behind the truck) closely follows the Bus until the Bus cannot proceed further.
If I could move forward, it would be possible for other people behind me to move forward to create space for the Bus to get past the parked car.
Unfortunately the truck behind the bus is now preventing me from doing so.
We are now gridlocked!

Fortunatly, I am in the LC, so I am actually able to break the gridlock by mounting the (Higher than normal) kerb and drive up onto the 30 degree angle grass bank to create enough room for everybody to start moving again.
But really, If I had been in my car (E36 compact), I wouldn't have been able to do this and we would probably all still be there fuming.
As it is, I still might have risked damaging my tyres mounting the kerb (They are road SUV tyres, Not rock crawlers)
And in any case, this situation shouldn't have arisen in the first place if the Rancid, Festering, Chum Buckets behind me hadn't "queued" adjacent to the parked cars.

[/Rant]