"gareth" wrote in news:lthnu9$ilc$1@dont-
email.me:
There have been designs published in Brit of using the steel of
wind-up tape measures, and this could be a potential starting point
for any discussion, by the use of flat metal tape.
I suspect my notion is not new, but what about a coil of wire, some well-
spaced trees, a long lanyard, a tennis ball, and a spud gun?
Someone will likely have one they prepared earlier, so I won't put the bits
together.