Tagul.com

Below is an example from tagul.com.  It is similar to wordle and tagxedo.  Of all three applications, I prefer tagxedo because you have more control over the final product.  This particular word cloud was made from a copy and paste of Grateful Dead songs.  I found that there were too few shapes and options with this tool.  Once my students finish their tagxedos, I will upload so that you can see the difference.