If you get an email like this do not click the link and sign into your PayPal account or you will give hackers direct access to your account.
This is a brilliant scam actually. Basically they send you a message that you received a huge amount of money which peaks your curiosity. You then log in (to hacker servers) and take a look, providing them with your username and password.
Then your account is hacked. If you receive a message like this don't click the link.
(If you're too curious and you have to check, open a new browser window and log directly into PayPal. )
The reason why this is so effective is they do a great job of spoofing Paypal's email. See the picture below.