gistfile1.rb

require "google_util"

consumer = OAuth::Consumer.new('anonymous', 'anonymous', {
  :site => 'https://www.google.com',
  :request_token_path => '/accounts/OAuthGetRequestToken',
  :access_token_path => '/accounts/OAuthGetAccessToken',
  :authorize_path => '/accounts/OAuthAuthorizeToken'
})

## I have also tried the above with :site => 'https://apps-apis.google.com'

request_token = consumer.get_request_token({}, {:scope => 'https://apps-apis.google.com/a/feeds/user/#readonly'})

puts request_token.authorize_url

access_token = request_token.get_access_token(:oauth_verifier => THE_TOKEN_YOU_GET_FROM_THE_SITE)

puts access_token.token
puts access_token.secret

client = Google::Client.new(access_token, '2.0')

feed = client.get('https://apps-apis.google.com/a/feeds/visualfaq.com/user/2.0', {  
  'xoauth_requestor_id' => "admin@visualfaq.com",  
})

## I get RESPONSE IS #<Net::HTTPForbidden 403 Invalid OAuth signature. readbody=true>