This, more than anything, has improved my productivity an embarassing amount (w/ the scala repl)

clipboard.scala

import java.io.{PrintWriter, OutputStreamWriter, BufferedOutputStream}

// copy given string to the mac clipboard by launching pbcopy in a subprocess
object Clipboard {
  def pbcopy(string: String) {
    val pb = new ProcessBuilder("/usr/bin/pbcopy")
    val p = pb.start()
    val stdin = new PrintWriter(new OutputStreamWriter(new BufferedOutputStream(p.getOutputStream)))
    stdin.print(string)
    stdin.close()
    val exitStatus = p.waitFor()

    if (exitStatus != 0)
      throw new RuntimeException("pbcopy process exited with status" + exitStatus)
  }
}

Nice! Here's a bit more concise version of that, too:

import java.io.ByteArrayInputStream
import scala.sys.process._

object Clipboard {
  def pbcopy(s: String) {
    "/usr/bin/pbcopy" #< new ByteArrayInputStream(s.getBytes("UTF-8")) !
  }
}

fuckin' show-off...