Python is nearly always installed, and that depends on nothing but the standard library. You can stick an alias in your dotfiles (I have, it's called "serve-this") and not have to worry about having twisted¹ getting to wherever your dotfiles get put. (I distribute my dotfiles over git/github, so it's really easy to move them around. More work to get Twisted.)

¹Or Ruby… or Go…

    package main

    import (
        "flag"
        "net/http"
    )

    var serveDir = flag.String("d", ".", "Directory to serve from")

    func main() {
        flag.Parse()
        panic(http.ListenAndServe("127.0.0.1:8000", http.FileServer(
            http.Dir(*serveDir))))
    }