The ESC or Escape key is basically a requirement to successfully operate many common Linux applications. At first glance the Droid keyboard lacks this functionality. This can be frustrating in VIM for example because you cannot exit insert mode once you have entered it.
Thankfully Motorola has included an ESC key, but its location is not obvious. To send the ESC character simply press the center of the directional pad twice. Hopefully this will save many of you headaches in the future.