i read someplace that a Slinky pulled out to it's max size could be used!
Yep, most any type of metal wire will work. However, it works (propagates) better when it is
roughly a multiple (such as 1/4 or perhaps 1/3) the length of the wavelength you are transmitting on. Distance above and relative to ground (and several other factors) are key variables also.
Reception across a much wider range can be achieved by a much more generic antenna.
Follow some of the ham groups and you'll find there are people who spend a good deal of their time modeling expected antenna performance and have discussion on difference of opinions about antenna design and performance as heated as anything else.