I use script/console a lot. It's a great way to learn about the Rails API, inspect objects, and get really good with ActiveRecord subtleties.

Yesterday I was doing this in script/console:

>> Product.find :all, :order => 'title asc'
=> [#<Product:0x342ee58 @attributes={"title"=>"Another", "id"=>"2", "released"=>nil, "version_number"=>"1.0"}>, 
#<Product:0x342ee1c @attributes={"title"=>"My Product", "id"=>"1", "released"=>nil, "version_number"=>"1.5"}>]

Good, there's a couple of products in my development database to play with. I wanted to get all of the titles in an array, sorted in ascending order. So I need to take the results of my previous statement and call collect on it - so I was about to do this:

>> Product.find(:all, :order => 'title asc').collect { |product| product.title }

With irb history installed, I can just hit my up-arrow to recall the previous statement. But I'd still have to edit it, to insert the parentheses, before I could append the collect iteration code. So what does a lazy person do when confronted with a task that might take a second or two? Why, spend a lot more time googling for a better solution, of course.

Sure enough, after a few minutes with my good friend Google, I found it:

>> _.collect { |product| product.title }

Yes, that's an underscore character in front of the .collect. In irb (and hence, script/console), an underscore is a kind of global variable that holds the last result. So in my case, it represents the collection that I had just found. You can also capture it in a variable if you want:

>> products = _
>> products.size
=> 2

Just a tip for anyone out there that's just as lazy as me.

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