Its interesting to know what other peoples answers are to this question. A lot of people claim that they have seen aliens on earth and the government is trying to cover the stories up and stuff but personally I don’t think they came to earth. I kinda do have a feeling that there is something out there in the universe besides us earthlings but I don’t think they payed earth a visit.
Would love to know what you guys think…… leave your answers in the comment section below or on twitter and ill be making another post on my blog and ill write your answers to the question 
there is a video of people from various military and some civilian specialist who witnessed some incidents that confirm the existence of other life forms, its two hours long http://youtu.be/7vyVe-6YdUk
There is a lot of evidence that suggests “aliens” have visited Earth… You should check out thrivemovement.com, its an eye opening and absolutely incredible documentary that brings this up.
I’ve seen a cow with 5 legs once but aliens hmm
http://en.wikipedia.org/wiki/Paul_Hellyer Interesting guy with solid background. Check the ” Peace In Space and UFO Advocacy ” section of the wikipedia attachment. Also, there are clips of him speaking on youtube.