Dropbox seems to be a good way to share files. You can make it a public folder, and increase your space just be inviting more people to use Dropbox. I have nearly 10GB in space all free. I sometimes have to clean it out with large videos I am no longer sharing, but it’s an option.
You can also you Facebook. Basically, upload the photo and right-click on the photo. It will give you the option for the ‘Copy image URL’. Then you just paste it here when you post.
Example, direct from my Facebook profile pic: 
David Cole - EKN Managing Editor