So many people have asked that question,and honestly its a dumb one.But its our job,to help you,so i made this thread.
There are many ways to hack an email:

Phishing
Phishing is a way of saying keylogger but in an other meaning.Let’s say you want to create a hotmail phishing page.The page should look
exactly like the real one.
How does it work:
You can download/make a replica of the website you want to phish.And save is as HTML.When you’re done with that,you have to find a way
to upload the HTML.Best way is a Website.Like Piczo/Blogspot.When thats done the user types his/hers username and password.And automatically
it will be sent to you by mail.And there you have it,that’s Phishing.
Here Are Some Tutorials That Help:
http://www.hackforums.net/showthread.php?tid=15895
http://www.hackforums.net/showthread.php?tid=14154
http://www.hackforums.net/showthread.php?tid=12583
http://www.hackforums.net/showthread.php?tid=12468

Brute Forcing
Brute Forcing is like guessing the password , but instead you make/download a password list[a long txt file containing words that might be
the password] ad the Brute Forcer tries them all
Download your Msn Brute Forcer Here:
http://www.speedyshare.com/228815220.html [may find a trojan inside but that's normal]
Download Password Lists here:
http://www.hackforums.net/showthread.php?tid=15562

Keyloggers
Keyloggers is like phishing but is more simple.Its a simple .exe executable.When someone clicks it,the Keylogger auto downloads.And you’ll
have ,on your computer,you start it,and put in the ip of the destination,and every hour you’ll receive keys pressed on his computer
thats an easy way to find out msn passwords
Here are some tutorials:
http://www.hackforums.net/showthread.php?tid=15003
http://www.hackforums.net/showthread.php?tid=10365

Fake Msn
Fake msn is just a replica of Msn Messenger.Let some of your friends come over.And open up the fake msn.Let them type in ther
msn hotmail,and their password.Then they will get a troubleshoot , and their username/password will be saved in a .txt file in C:\
Download here:
http://www.savefile.com/files/1357897

Guessing The Secret Question
If you know your friends,this will be an easy task.Go to http://www.hotmail.com and click forgot password,then put in the email address
and then the CATCHA code,reply on the secret question,but beware because you have like 3 tries only.