On Ruby 1.8.7 irb:

```ruby
>> { '.tar.gz' => Array, '.msi' => String }.find { |k,v| "test.msi".end_with? k }                                                                                                                           
=> [".msi", String]
```

On Ruby 1.9.3:

```ruby
irb(main):001:0> { '.tar.gz' => Array, '.msi' => String }.find { |k,v| "test.msi".end_with? k }
=> [".msi", String]
```

So the `last` call is to get at what was the value half of the key/value in the hash. I'm open to more elegant ways of doing it, but it seems to work.