I use the public folder in
Dropbox because it is super easy and Dropbox is useful for so many other things. Just put the file in your Public folder and it automatically uploads, then right click the file in and one of the drop box choices will be "Copy Public Link"
Note: The Dropbox link is a referral link, since if you refer more people you get more space to store things (up to 8GB). Also, if you sign up via a referral link you get more space to start as well.