I almost got taken out by Prius yesterday. 4 lanes each way including HOV. I'm in the center, doing ~68, Prius is in HOV. I had caught up to it as I was traveling a couple mphs faster when it moves over to the passing lane. I keep watching because I "had a feeling". My FL fender was was just over its RR, still in our own lanes, when it starts coming into my lane! I hit the brakes, to get out of range of Prius' bumper, and lean on the horn. Driver acts like I'm not there and is about half into my lane, now. I keep on the horn and he finally moves back into his lane. No blinkers on either lane change, too.
That tweaks me...the no blinkers thing. Total lack of courtesy. On the other hand, so many drivers use the blinker as if it gives them the right to the space they want to move into. As if the few square inches of a blinking light, instead of the 1.5 - 3 ton vehicle suddenly moving into a lane, is something the driver now behind them is worrying about!