Naval Railgun prototype undergoes first tests...

[TheWraith]

16. Similar ideas have been in the ether for a long time.

Going back at least as far as the 1960s, there's books that have postulated the idea of using magnetic acceleration "catapults" which function basically the same as this as a cheap means of launching things to orbit. You'd have to have a very large one, though, if you wanted to launch anything of useful size at a speed which wouldn't turn the contents--say, people--into pulp. But you're right that a smaller version could theoretically be used for supplies, or even for small solid-state satellites which can be assured of surviving those kinds of G forces.

Ironically, in Heinlein's "The Moon is a Harsh Mistress" the process we see here is kind of reversed; a mag launcher designed for cargo shipping is actually ad-hoc converted into a missile launcher. Albeit using 100 ton missiles.