DIY Electric Bike

Here's a nice write up on building your own electric bike. The discusison about various problems with motors, gear ratios vs chain speed, power controller ratings, and various suppliers for all of the parts is very good. If the traffic wasn't so lethal around here, something like this would fit my bill for my daily commute (2.5 miles). However, six months ago a researcher here was killed riding his bike across a street at a cross-walk by someone running a red light, and many of the roads here are 4-6 lanes and sometimes lack even sidewalks. That's a little too Road Warrior for me to chance it - unless you mount machine guns/rocket boosters or something. Then it would be safe.