Christmas is coming closer, so here is my contribution to put you in the right mood. It is a blog hitcounter, that rings a bell. Literally. It puts a smile on your face, every time someone hits your blog.

It consists of an Arduino board, a bell, a servo and a couple of lines of code in c, python and php. Most parts are fairly common and should be easy to get.

This instructable will show you how to use an Arduino to send and receive a variety of MIDI messages so you can start building your own MIDI controllers and instruments.  First I'll talk a little bit about MIDI protocol, if you're just looking for sample code skip ahead to steps 5-9.

If you know absolutely nothing about MIDI note, velocity, and pitchbend or are confused about what MIDI does and why you would want to use it, check out my What is MIDI? instructable.

In this Instructable, I will show you how to make your Christmas lights turn on when there is someone in the room using an Arduino, relay module and a PIR motion sensor.
I made this because I wanted the lights on my miniature Christmas tree to turn on to greet someone when they opened the door.