Here is another useless but cool looking must build gadget for every romantic geek. Let me introduce PIC microcontroller based three axis laser spirograph.
It is a very small portable character projector, based on inexpensive laser diodes, projecting a single line of text onto nearby walls and tables. It might be useful for projecting text from portable and wearable devices like cellhones and PocketPCs that will be connected, e.g., via wireless serial connection.
Built with high intensity 8000 to 11000 mCD white LEDs, these lamps sit directly on top of a 12 volt 2.7 amp-hour SLA battery and works well on a dining room or makes a great reading light with an adjustable head angle.
Here we present two open-source, do-it-yourself, microcontroller-powered holiday electronics projects, A micro-readerboard Christmas tree ornament and a mini-LED Hanukkah menorah.
If you are thinking about installing a fiber optic sky ceiling you really need to plan for it, otherwise, you will have a difficult time making it look good.
The first time I saw a projection clock (a friend had shown me his projection clock, which he used to project the time on his bedroom ceiling), I knew I could easily build my own by converting a watch with an LCD display. I bought a very very ugly watch in a dollar store. So ugly that it really is unwatchable) At least it's easy to disassemble.
A Multifunction Led Display is the easiest way to create your own information system display .This display is a kind of colored LEDs controller through the parallel port using a very, really very easy scheme.
This project is a small (3.8"x2.1") PCB that allows very simple control of upto 13 RGB full spectrum LEDs. LED settings (color, state, brightness) can be stored on the board as power-up defaults or can be set/changed over a serial link (RS232 or SPI) with a very simple command protocol.
It's nice to have a bit of colour in your house for style reasons, so here are some neat little PCB's that accommodate a mixture of red, green and blue LEDs giving you the option of controlling the colour they emit. They are designed to fit into standard MR16 downlighter frames for convenience of mounting.
Use solid-state relays to blink the lights on your tree in time with music.