How to make a led lamp?

Light should be equal to a 40watts fluorescent tube?and whether it would be a vice idea, ?

light is measured in lumens 40 watt bulbs range from about 130-280 it depends on what you want the best thing for you to do would be to go to radio-shack and pick up a super-bright led (around $5) check the back to see about how many lumens you should be able to power it with two D-cells without much resistance needed if you want to power it from the wall, I can't really help you that's a lot more trouble than it's worth, anyways need any more help?