This is a wrapper for couple of things I usually do with SF

Installation

Prerequisite is having git, ruby and gems installed (also you should have XCode installed since there probably will be need to compile some C code in the background).

gem install bundler
git clone git://github.com/fluke777/salesforce.git
cd salesforce
bundle install
rake install

Grabbing fields of a module

Since Force.com explorer cannot search in fields and I love my text editor too much. I created a command how to download the list of fields

require 'rubygems'
require 'salesforce'

client = Salesforce::Client.new('login', 'pass+token')
fields = client.fields('Account')

# if you are looking for a specific one
fields.grep /Customer/i

# if you did not want a api name you can do whatever you want with describe. For example here I am grabbing label
response = client.describe('Account')
response[:describeSObjectResponse][:result][:fields].map {|field| field[:label]}

Downloading data

You can grab easily some data. Paging is implemented so it will download all the data.

# grabbing into array (this should probably be the default and it should return the field rather than pasing a reference inside)
x = []
client.grab :module => "User", :output => x, :fields => 'Id, Name'
x.count

# storing it into a file as CSV is easy as well
require 'fastercsv'

FasterCSV.open('my-csv.csv', 'w') do |csv|
    client.grab :module => "User", :output => csv, :fields => 'Id, Name'
end