One of my favorite memories of flying as a kid was United Airlines’ channel 9 feature that lets you listen to cockpit air traffic control communications. I’d even pester my parents to buy the $2 headphone tube (remember the rubber tube type?) before takeoff so I could listen from taxi to landing. Channel 9 and a window seat kept me occupied for hours and it still does.
You can recreate the experience with LiveATC.net; it lets you listen into different ATC channels around the world. I like ORD Tower, ORD Approach, and SFOTower, but there are lots to pick from. The site uses ground based scanners, so their coverage is not complete. I like streaming it when working on occasion; its good background noise that helps me focus. I’ve used it at BOS too while watching the runways from my favorite spot in all Massachusetts, the walkway between B and C gates. There is a great view of the field, rocking chairs, and power outlets. Best place to kill time at BOS since there is nothing really to do post security.