Arduino is very rich in its shields so there is another fast and great project – WiFi controlled Arduino robot. The platform is pretty simple – mainly made of wood. Interesting part is that Arduino is equipped with WiShield from AsyncLab’s that allows controlling bot remotely via TCP.

Robot platform can be controlled via Zipit or joystick. And of course it can perform standard movements autonomously. Project may be a great start to get used to programming WiShield that may push projects to a new level.

Don’t hurry to throw old stuff away – they might be interesting and useful for some projects. Check out this alarm system built around modem. Alarm system itself consists of PIC microcontroller and PIR sensor. When someone is detected in the room microcontroller dials a number to alert the user.

Microcontroller communicates with modem via RS232 interface. There is a DS275 chip used instead of well known MAX232 – this way circuit becomes even simpler as there is no need for caps. As there is only one sensor at present probably it would be great to expand project to secure more objects by adding more detectors.

This LED wristwatch uses old fashioned LED displays that look really cool. They have some similarity to nixies if look closer. The heart of watch is PIC16F628A microcontroller with separate oscillator to keep track of time.

The watch has also two buttons for setting time. It is powered with two button batteries. In fact this is pretty simple watch with no fancy features but it looks great when it sits on a hand.

Probably you know that prime number is a natural number that can be only divided by 1 and itself. So these might be 2, 3, 5 and so on and on. But how to find large numbers that are prime numbers. OK Lets leave theory and move head to the project.

Prime number generator is based on ATtiny2313 microcontroller and continuously discovers prime numbers up to 13 millions. So further numbers are discovered slower and slower, because microcontroller has to check every number by doing simple math. Interesting solution of displaying numbers is that they are represented as a grid table of powers of two. By adding these number light by LEDs lets you to find number in decimal format.