Getting inputs from an USB Keyboard

Hello everybody
I'm looking for the best way to get data from an USB keyboard connected to an Arduino board. For instance : if I type "A", some led brights, and if I type "B", it's some other that does.
I saw a workaround for PS/2 keyboards but I guess it might be easier with USB ? Or is it not ? (and is there a way with one USB only boards ?)
Thanks in advance for any answer or link,...
jn

To connect a USB peripheral to an Arduino you need something like a USB Host Shield.

Some boards have several USBs, I guess it's the same ? But then, how to access to what the keyboard sends ?

The Arduino MEGA ADK (http://arduino.cc/en/Main/ArduinoBoardMegaADK) has a built-in version of the USB Host Shield.

To program the USB Host chip (MAX3421E) read the datasheet for the chip.