[Techtalk] When might I use 'hostid'?

[hobbit at aloss.ukuu.org.uk]

In a reply on newchix, I was looking for examples of the little
sh-utils and fileutils nifty programs you rarely need but which
occasionally find to be the exact thing you want in shell scripts
or amazing one-liners at the shell prompt.

And in looking at rpm -ql sh-utils, I found the lines
/usr/share/man/fr/man1/hostid.1.gz
/usr/bin/hostid

And this sounded useful (except for the bit about the answer
being in hex). Trying it, I got

[hobbit at aloss hobbit]$ hostid
7f0100

..as did half a dozen other people on IRC. 

What is this command for? When would I need to use it? Is it a
"handy for shell scripts when put within back-ticks" thing? Is
the fact that over half the (small) sample of people on IRC to
try to got the same answer a bug?

What's it _for_?

Telsa