title: Adding text to a plot with a specified color for each letter
body: <p>I'd like to add text to a plot, where each letter in the text has a specified color.</p>
  
  <p>I know <code>addtable2plot</code> of the plotrix package allows adding a table (<code>data.frame</code> or <code>matrix</code>) to a plot, and allows the background colors of each cell to be specified. Unfortunately the same does not seem to apply for the text. So I was wondering if anyone has an idea how to achieve this.</p>
  
  <p>For example:</p>
  
  <pre><code>plot(density(rnorm(1000,4,1)))
  </code></pre>
  
  <p>would be my plot</p>
  
  <p>and then I would like to add this text:</p>
  
  <pre><code>c("T","T","A")
  </code></pre>
  
  <p>with these corresponding colors:</p>
  
  <pre><code>c("red","red","blue")
  </code></pre>