title: Legend placement, ggplot, relative to plotting region
body: <p>Problem here is a bit obvious I think. I'd like the legend placed (locked) in the top left hand corner of the 'plotting region'. Using c(0.1,0.13) etc is not an option for a number of reasons.</p>
  
  <p>Is there a way to change the reference point for the co-ordinates so they are relative to the plotting region?</p>
  
  <pre><code>mtcars$cyl &lt;- factor(mtcars$cyl, labels=c("four","six","eight"))
  ggplot(mtcars, aes(x=wt, y=mpg, colour=cyl)) + geom_point(aes(colour=cyl)) + 
  opts(legend.position = c(0, 1), title="Legend placement makes me sad")
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/i4H6s.png" alt="enter image description here"></p>
  
  <p>Cheers</p>