This is a Vertical Axis Wind Turbine which uses wind energy to drive things like air and water pumps for cooling, irrigation and similar, or an alternator/generator for producing electricity.
Note: this tutorial is also available at http://solarflower.org/tutorial.php?lang=en&tut=vawt with a slightly more usable layout.
The turbine uses the 35-40% mechanically efficient Lenz2 lift+drag design. It is made entirely from scrap materials except for the bolts and pop rivets, and should cost about $15-$30 for the six vane version, which can be made by two people in six hours without much effort.
The three vane version has been successfully survival tested to 80 km/h sustained winds and the six vane version to 105 km. Both will do more, but exactly how much has not yet been ascertained.
Full power curves have yet to be calculated for this particular build, but according to Mr Ed Lenz's calculator (http://windstuff.org/calc/calc.php) a six vane at 0.93 meters diameter and 1.1 meters high with a 90% efficient alternator should produce at least 135 watts of electricity in a 30 km/h wind, and 1.05 kilowatts at 60 km/h.
The materials listed in this tutorial are to make the three vane version. Double everything except the bike wheel for six vanes.
4mm metal drill bit
Craft knife / scalpel / exacto
20mm x 20mm angle aluminium
About 1 meter long, an extra ~30cm length can also be handy. To be used for ruling and bending.
Probably 7mm, 15mm and 17mm - to fit your M4 nuts and the nuts on the bike wheel axle
Bike Cone Spanner
4 Clothes Pegs
Springy or the other kind.
A small bit of wood
For drilling into.
Computer and printer
Low quality black and white is fine.
2 pieces A4 paper
12 Aluminium lithographic offset printing plates
These are pure aluminium sheets used in a printing process fairly common with newspapers and magazines. A medium sized printing company may scrap hundreds of plates every week, so it's usually easy to pick them up cheap. Ring around any local companies offering offset printing.
This tutorial is for plates which are 67cm wide by 56cm tall. There doesn't really seem to be any size in particular which is standard, if you can only get plates which are larger than 67cm then either scale up the measurements (though that is the size which best fits a 27 inch bike wheel, which is generally the largest you can get) or trim the plates down to that size. If you can only get smaller than scale the design down and use a smaller wheel.
The 56cm length really doesn't matter at all. The taller the vanes the more energy you'll get. The relevant steps in the tutorial will tell you how to accommodate other lengths.
126 4mm diameter pop rivets
About 5mm long.
18 M4 bolts and nuts
About 15-20mm long
18 spring washers
To fit the M4 bolts
4mm inner diameter to fit the pop rivets, about 10-15mm outer
27 inch bike wheel
Exactly how bike wheels are measured is slightly complicated, basically you want one which is 64cm total outer rim diameter. You can use other sizes for smaller turbines, adjust the other dimensions accordingly.
It doesn't matter if it's a bit rusty but needs to run smoothly and not wobble. You don't need the tire or inner tube.
6 bike wheel spokes
Any length. Some kind of thickish wire or similar would also suffice.