Trace:
C:\Documents and Settings\apenneba\Desktop>type hello.clj
(ns hello
(:gen-class))
(defn -main [& args]
(println "Hello World!"))
C:\Documents and Settings\apenneba\Desktop>clj
Clojure 1.2.0
user=> (load "hello")
nil
user=> (hello/-main [])
Hello World!
nil
user=> (System/exit 0)
C:\Documents and Settings\apenneba\Desktop>clj hello.clj
C:\Documents and Settings\apenneba\Desktop>