I want to see a list of all outgoing HTTP requests from my desktop. I think it should be possible to monitor HTTPS hostnames as well for local clients using Server Name Indication (SNI).
OS X has a nice GUI utility called Little Snitch, which is a per-app HTTP monitor and firewall rule front-end.
I would settle for a nice terminal utility.
tcpdump is overkill as I just want to see where the traffic is going in real-time and not the transmitted data. Ideally, I would like to see what process made the request as well, but just seeing what dials home would be a nice start.