you obviously wouldnt have to use a heart, but an LED chaser on a mouse would look pretty cool. the only problem you might have would be a space issue, you might even have to cut a stripboard or PCB to fit nice and snug. personally, i only managed to fit a single flashing 555 timer circiut in one, and it was still pretty cool.

But yes, out of interest, what type of resistor did you use Pasteler0? If you don’t know the value just give the colour bands on it in order.

you can see this is the first picture, where the mouse wire connects to the mouse, there is like 5 wires.