more on lights
many folks like to work with two sets of 50 because the lights are easier to thread that way. just remember to make sure they are plugged in securely to each other (always test!) before you put the ball together.
you can find great sources for many different kinds of mini-lights on the internet. Just google. One good source I've used is christmasdepot.com
sparkleballs look great in all one color. you can also find lights with white electrical cord and different lead lengths from first light to plug.
"chasing lights" come in different counts. you'll have to do the math, but each cup will have 2 or 3 lights in it.
Don't be afraid to experiment with different kinds of lights-- especially if you find strings on sale after Christmas.
when you make a mini-sparkleball, don't use more than 70 lights or there will be too much electrical cord to fit in the middle.