I was fascinated by how Madrid dealt with this problem. The population of Madrid is a little above 3 million, while the Madrid Metropolitan area counts over 6 million! Many people living in the surrounding cities travel to work in Madrid. Since the rush hour is horrible in the morning towards the city, and in the afternoon in the direction heading outside, they created (using concrete walls) another central lane (between the two directions) which is:
However, it can be used only by public and private transportation, including taxis, car sharing, etc. That means that you can use it if you are traveling with someone, and not alone.