Lightweight IEEE802.11 wireless LAN analyzerhttp://br1.einfach.org/tech/horst/
horst is a small, lightweight IEEE802.11 WLAN analyzer with a text interface.
Its basic function is similar to tcpdump, Wireshark or Kismet, but it's much
smaller and shows different, aggregated information which is not easily
available from other tools. It is made for debugging wireless LANs with a
focus on getting a quick overview instead of deep packet inspection and has
special features for Ad-hoc (IBSS) mode and mesh networks.
It can be useful to get a quick overview of what's going on on all wireless
LAN channels and to identify problems.