// for browser using, this code requires javascript 1.7+

var arr = [
  { foo: 'bar', lorem: 'ipsum' },
  { foo: 'bar', lorem: 'ipsum' },
  { foo: 'bar', lorem: 'ipsum dolor sit amet' }
];

arr = arr.map(JSON.stringify).reverse() // convert to JSON string the array content, then reverse it (to check from end to begining)
  .filter(function(item, index, arr){ return arr.indexOf(item, index + 1) === -1; }) // check if there is any occurence of the item in whole array
  .reverse().map(JSON.parse) // revert it to original state

console.log(arr); // [ { foo: 'bar', lorem: 'ipsum' }, { foo: 'bar', lorem: 'ipsum dolor sit amet' } ]