A simple ruby script that will display the weather for a given zip code using Yahoo's weather API.

weather.rb

require 'net/http'
require 'rexml/document'

puts "Enter your zip code to get today's forecast"
print "Zip: "

zip = gets.chomp

if (zip.nil? or zip == 0)
  puts "Invalid zip, program exiting."
  exit 1
end

feed = Net::HTTP.get 'weather.yahooapis.com', "/forecastrss?p=#{zip}"

if (feed.nil? or feed == 0)
  puts "Yahoo! Weather unavailable, program exiting."
  exit 1
end

xml = REXML::Document.new feed

city = xml.elements['//yweather:location'].attributes['city']
region = xml.elements['//yweather:location'].attributes['region']
country = xml.elements['//yweather:location'].attributes['country']

condition = xml.elements['//yweather:condition'].attributes['text']
temprature = xml.elements['//yweather:condition'].attributes['temp']
degrees = xml.elements['//yweather:units'].attributes['temperature']

puts
puts "Forcast for #{city}, #{region} #{country}"
puts "#{condition} at #{temprature}#{degrees}"
puts

exit 0