honeypot sw for nmap testbed?

I'm looking in to trying to make a pleasant playpen for someone
trying to learn nmap.

It seems to me that some honeypot software ought to be a nice
starting place, for creating something that looks like a big,
interesting, diverse network on e.g. 127.1/16.

Does this sound realistic, or am I completely out to lunch on what
things like honeyd are good for?

My real fantasy would be to craft up some scripts that take nmap's
OS and application signature databases as input, and build random
nets populated with machines that look like all kinds of stuff that
nmap knows about. Anybody heard of anything like this? Sort of
vaguely like what stick does to snort.

Thanks,

-Bennett