I saw Mike Knuepfel's Keyboard Frequency Sculpture a few weeks ago and thought it was an excellent idea for visualizing letter frequency data.
The height of each key corresponds to how frequently that letter is used in samples of English writing.
I wanted to see how the layout of the most frequently used letters on a QWERTY keyboard compared to those on a Dvorak keyboard. Unfortunately, I'm no sculptor, and I couldn't see an easy way to slice and edit the original image to rearrange the keys, so I decided to use a color mapping instead.
The images below were created using the same letter frequency chart as the original sculpture. Pure blue is for the least frequently used letters, while pure red is most frequent.
Note that the majority of the most frequently used keys are on the home row in the Dvorak layout, but they're scattered all around on a QWERTY keyboard. The QWERTY layout originated in the very early days of mechanical typewriters, so the keys were arranged such that common two-letter combinations were placed on opposite sides of the keyboard so that the mechanical parts would not jam. The Dvorak layout was designed to reduce finger motion in order to increase typing rate and decrease errors. Despite these advantages, the Dvorak layout has still failed to catch on.