The image above is a screencap, but you can view real-time positions of commercial aircraft at Flightradar24. And not just for the U.S. Here is the current map of flights over Europe -
And Brazil -
The maps at the source link are zoomable and interactive with a variety of data.
As one watches these icons move, one can't help but wonder what effect all that traffic has on air quality. I remember after the 9/11 air traffic shutdown, the U.S. was reported to have record clear skies free of contrails, and measurable increases in solar energy at ground level.
Addendum: Reader Aleksejs provides the link for a similar website for tracking ships-
- with interactive features including photos of the vessels.