I love using a USB mouse and numeric keypad on my A600! Having a mouse plugged into the side, where my mouse pad is, was annoying and got in the way of my hand. Now my USB mouse is plugged in behind the A600.
Oh, and playing DOOM on the A1200 with a USB control pad really beats using the keyboard, with those shoulder buttons to strafe and all the fire buttons and Start button supported.
ANAIIS ROCKS!