Courtenay and bousquet are behind Cartographer that allows you to integrate Google Maps in your Ruby on Rails application with no effort. A few API tastes:

<%= gmap(:mapname=>"my_map", :width=>"50", :height=>"120") %>

<%= gmap(:width=>"500", :height=>"500", :type=>:satellite, :point=>[-122.14944, 37.441944]) %>

<%= gmap(:mapname=>"foo", :white_div=>{:background_color=>'black', :height=>'40'}) %>

Pretty nifty stuff! See also bousquet’s announcement.