You can use an old computermouse and turn it into a cool light! Really geeky - isn't it? :-)

Sorry that I don't have more pictures for the single steps, because when I made this, I've never heard about instructables.com - but I hope you get the basic idea and it's a real simple project, so it shouldn't be a problem to make your own LED computermouse light.

And it's my first tutorial.

## Step 1: The Parts You Need

You'll need:

Components:
an old computermouse
a LED (3 mm) with your favourite color - I used a white LED from the German store http://www.led1.de with 12.000 mcd
a resitor - depending on your LED - calculation at the next step
a switch
batteries - i used two 1,5 volt AA batteries
a battery clip - to hold my two AA batteries

Tools:
hot glue
soldering-iron
screwdriver
driller

## Step 2: Calculate the Resistor

I wanted to use two 1,5 volt AA batteries. My LED needs 2,95 volt - so there are 0,05 volt left for the resistor. The LED needs 20 mA.

When you buy a LED you'll see UF for "U Forward" and IF for "I Forward" - these are the values you'll need.

So let's calculate the resistor:

R = U-Resistor / I-LED
R = 0,05 / 0,02
R = 2,5 Ohm

So therefore I used a 2,2 Ohm resistor.

## Step 3: How to Build

First I unscrewed the mouse and removed all those electronic parts. Then I removed the mouse wheel and drilled a whole which was big enough for the switch and glued the switch. Next I replaced the cord and glued the LED there. Then I connected the parts (switch, battery clip, resistor, LED) together - look at the picture.
Nice idea! At first I thought this was for a working mouse, one that you could use during the time the mouse is in use or not. Might give me an idea... Nice job, +4.5/ 5 stars.
ooooooooooooooo
nice, but i bet you could have do it on the mouse button
man that's such a good idea! I didn't even think about it! *OMG* thank you for that comment! oh i think another dead computermouse would be modified into a light! maybe one of those two colored LEDs. i have two mouse buttons - when I press the right button maybe green light and when I press the left button then maybe red light! very nice idea - I think i should make this!<br/>
i will try to, i have a becolor(right/green) led but pressing both button would make a short, so watch out. got 100 for 10\$ on ebaaaayyy!