It is fun to imagine how you could set up a price structure that incentivizes the right things to prevent traffic jams.<p>For example:<p>* A small per-second fee that is inversely related to the distance between your vehicle and the vehicle in front or behind you, whichever is closer. Maybe the distance scale would be dynamic based on speed, maybe measured in &quot;estimated stopping time&quot;, such as (just as one wild example) a certain fee for being at 100% of safe estimated minimum stopping distance, a smaller one for 200%, a higher one for 50%, negligible or no fee for more than 1000%,<p>* A penalty fee for changing lanes. In dense or stop and go traffic, changing lanes imposes a pretty large cost on nearby traffic, as both lanes are stopped for a bit. Grass-is-greener temptation causes many drivers to change lanes, which quickly eliminates any sought advantage, but makes traffic worse as drivers essentially take up double space.<p>* etc?<p>Then dynamically tune the fees to get the desired result. Watch as frugal drivers economize by<p>* avoiding tailgating and unnecessary lane changing<p>* (because of the &quot;minimum of distances&quot; rule) learn to, in denser traffic, balance their available space between front and rear neighbors.<p>* are loathe to go too slow without making it easier for faster traffic to pass (if you want to enforce speed limits, maybe the distance-to-rear-neighbor cost should only be enforced when travelling below the speed limit?)<p>* Per-second instead of per-mile fees encourage drivers to avoid already jammed areas<p>As for hardware -- I guess the kind of hardware needed for adaptive cruise control &#x2F; lane maintenance&#x2F;merge assist now found on fancier vehicles is sufficient to measure and operate this (as long as few people successfully hack their toll measurement system, which I honestly think is realistic).