I don't know whether anyone else experiences these things, but as I commute five days a week, it happens to me quite often:

1) You come to a four-way stop, and even though you were the last one to arrive there, and you are observing the right-of-way rules yourself, all of the other cars wait for you to make the first move.

2) You come to an intersection in which you have a stop sign/light, but the cross traffic does not. Someone stops (they don't have a stop sign/light) to let you cross.

I suppose I should be appreciative that they are being considerate, but I wish that they would just follow the rules-of-the-road. I am NOT a pedestrian; I am bound by the same rules (at least in Oregon) as those of cars. In the case of #2, their action often endangers other drivers behind them, who aren't expecting someone to stop where there is no traffic control devise, or the drivers in the opposing lane from them are oblivious to their act of kindness, and so keep driving, making it impossible for you to cross, anyway.

Depending on my mood, I sometimes just give in and go, or I look at them and yell ("Go, go, go!") and wave them onward.