Xobin - Most Comprehesive Pre-Employment skills testing and Psychometric Assessment Platform.
Interviewlab - Stop wasting your time searching job interview questions
Myskillwall - The best tool to prepare your job interview
Product Management Exercises - A repository of product manager job interview exercises
Interviews on Skype - Test candidates using a real-time code editor over Skype
The PM Interview - Practice PM Interview Questions (w/ timer).