You can get those for the sigaret lighter of a car, then they are 12 volts and need the appropriate adapter. So if you have a 12V output that would be good. Maybe they have 9V lamps for such lights.
Anyway, you can buy them in car-accessory(sp?) shops, they are used for map reading.
Alternatively you could just put a lights rope around your board, so close to christmas you can buy them everywhere and they work on normal net voltage. They are also waterproof mostly. Would light up your entire board in one go! Dont know if that would cause interference on the net youre using though.....