BrainBench.com one of the sites that I have come across which gives you access to free online tests. Anything good that comes for free is rare :-D.
Brainbench tests that are available for free. There are about 600 assessments and certifications that they offer, and a great way to try it. There are four types of free tests, to know and try them access the link below.
CLICK HERE FOR BRAIN BENCH FREE TESTS