The alternative which Drew posted might be a good alternative if you only have a smart phone. Register yourself with Flickr or someother photo-posting site and upload pictures there. Then go to the link on that site to "copy photo URL". You can then create a post here and use that URL for the image. This approach is common on many forums across the internet. Here's an image I posted on
bananas.org, displayed here using the image icon (little rectangle with gray mountains and yellow sky):
