A fun little toy for all ages ... or the beginnings of an experimental base for a few robot projects ...
A small robot head ... can be a R/C toy using a DSM radio and receiver ... or use a µController ... a BS2 or Propeller or Arduino etc...
Two Continously Rotating Servo Motors
(you can easily modify these $4 servo motors: http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=16269&aff=757677) or buy (http://parallax.com/product/900-00008 or for a faster robot; http://parallax.com/product/900-00025)
I use a Spektrum DSM Radio and Receiver, but there are many brands and price ranges ... most affordable is the Turnigy 6X ~$30;
or Turnigy 9X ~$50;
I've been using Pezio speakers for the eye's along with the Parallax HomeWork µController board, but you can use other sound modules too ... http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=9031&aff=757677 or http://www.hobbyking.com/hobbyking/store/__37885__Arduino_Compatible_MP3_On_Board_Microphone_Recorder_Sound_Module.html for a couple of choices ...
The nose is a 6mm diameter low power laser pointer element ... they can be found everywhere online and if yours is larger, just drill out the hole to the diameter needed ... up to about 16mm will fit nicely on the robot nose. To drive the laser at full brightness use a R/C relay on the landing gear switch this one is about $7; http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=40044&aff=757677
The bottom display is just three LEDs ... I use red because I have hundreds of them, but they can be any color or assorted colors ...
After printing I paint my parts using $1 bottles of finger nail polish ... it's more ABS compatible and much cheaper than hobby paint.
The final trick is to paint a scheme better than I paint ... then adjust the guts so that the robot is balanced by gravity ... drive it around and watch it flop forward 'n backward.