top-like utility for network connections usage

 pktstat displays a real-time list of active connections seen on a
 network interface, and how much bandwidth is being used by what.
 .
 It partially decodes HTTP and FTP protocols to show what filename is
 being transferred, as well as X11 application names. Entries hang
 around on the screen for a few seconds so you can see what just
 happened.
 .
 It also accepts BPF expressions.