Cartographer generates painless Google Maps for your Rails application.
In your controller:
def index
 @spots = Spot.find(:all) # Your Geocoded location model
 @map = Cartographer::Gmap.new("spots", :zoom => :bound, :controls => [:small,:scale], :debug => true)
 @spots.each do |spot|
 @map.markers << Cartographer::Gmarker.new(:name => "spot_" + spot.id.to_s, :position => [spot.lat, spot.lng], :info_window => spot.description)
 end
end
In your view
 <%= @map.to_html %>
You will need:
A Google Maps API key (put it in config/cartographer-config.yaml)
Geocoded locations (easily done with Geokit -- http://geokit.rubyforge.org/)
Current Version:
v0.1 08 May 2008
* Original Rubyforge version with some small edits
History:
Original Rails blog announcement is at http://download.rubyonrails.com/2005/8/30/cartographer-effortless-google-maps-in-rails, but the Rubyforge project page is dead. So I'm bringing it back.