Serious question: what kind of servo can you get for < $5? I recently built a robot, and spent $16/motor.<p>edit: never mind, the original site has a parts list. $2.69 each, he links here, but the site is down right now: <a href="http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=662" rel="nofollow">http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idP...</a>
I threw together something like this using scraps I had around.<p>Instead of using cardboard though, I used a piece of acrylic for the base. Then I got a couple of those blank expansion slot covers from the backs of PC cases, and bent them to make another stand-off platform on which I mounted a piece of ABS. On that I put a webcam and Pico-ITX SBC with a SDD affixed to the bottom of the ABS. An NiMH battery pack was put on the lower base between the two servos to keep the CG low.<p>The wheels were initially blank CDR's but they didn't get
very good traction so I eventually found some wheels for an RC airplane. I used a small caster wheel in back.<p>The moral of this story is always have scrap plastic around.
I have built so many small helpful things out of it like a stand for a 7" tablet on exercise bike, etc.
A friend of mine makes a nice light-following robot:<p><a href="http://www.hackerspaceshop.com/solarroboflower-kit-eco.html" rel="nofollow">http://www.hackerspaceshop.com/solarroboflower-kit-eco.html</a><p>Its not $10, but still pretty affordable, and a very fun project to do with kids ..