jQuery Form Fillers for instant (basic) form-filling action. Run through the browser console.

form_fillers.jquery.js

// Set text fields
$('input[type=text]').val('test');

// Set email fields
$('input[type=email]').val('test@test.com');

// Set combo boxes to 2nd index (in case first is blank)
$('select').prop('selectedIndex', 1);

// Set all checkboxes to checked
$('input[type=checkbox]').prop('checked', true)

// Set all date fields
$('input[type=date]').val('2015-01-01')