Macbook Pro 2011 Heat Problems
Open the computer (have a look at Youtube for instructions) and blow away all dust that has gathered. I use compressed air you can buy in a hardware store for this. If you haven't done it on a computer that is a couple of years old it can make a huge difference.

Good to do it before the summer (if you are located on the northern hemisphere). The problem is that the more the fan blows, the more dust it suck into the computer which makes the fan go even faster etc.