Sing is a little tool that sends ICMP packets fully customized from command
line. The main purpose is to replace/complement the niceful ping command
with certain enhancements as:

 - Send fragmented packets (Linux and BSD).
 - Send monster packets > 65534 (Linux and BSD).
 - Send/read spoofed packets.
 - Send many ICMP Information types in addition to the ECHO REQUEST type sent
   by default as Address Mask Request, Timestamp, Information Request, Router
   Solicitation and Router Advertisement.
 - Send many ICMP error types: Redirect, Source Quench, Time Exceeded,
   Destination Unreach and Parameter Problem.
 - Send to host with Loose or Strict Source Routing.
 - Use little fingerprinting techniques to discover Windows or Solaris boxes.
 - Send ICMP packets emulating certain OS: Cisco, Solaris, Linux, Shiva,
   Unix and Windows at the moment.

WWW: http://sourceforge.net/projects/sing/