Google Maps has to be the most popular way to find directions, be it driving directions, walking directions or public transit directions. However, many people do not prefer to drive cars and prefer to drive their bicycles to work.
In cities like New York and other locations, there are dedicated biker lanes, however, if you are travelling to a new destination it is pretty hard to find out beforehand which routes have proper biking lanes.
However, that is a thing of the past as Google Maps have now rolled out a new feature called "Biking directions", which will help users to find bike trails and dedicated bike lanes on maps. Google Maps has an enormous amount of data for bikers, which includes 12,000 miles of trails covering 150 cities within the United states.
I personally use Google maps to find walking directions and public transport directions while travelling within NYC, this new feature will definitely help me ride my bike more often with a proper trail.
If you are a biker, you can try out the new feature by visiting http://maps.google.com/biking.