With a Dropbox account, you can easily share any file to your iPad, and you can even use it to stream your video files that won't play in iTunes.
I've done a few tests and it's specifically Dropbox links that. As of today, any emails I send that have a shared Dropbox link pasted into them get trapped in the Comcast webmail/Xfinity Connect Spam folder, even though I've sent them from my own Comcast email address (using Outlook for Mac). This is a how to guide on how to share dropbox folders. One of the easiest ways to accomplish this is with a shared Dropbox folder. Often, when I am creating content for businesses, I ask the owner or rep I am working with to supply me with as many images as possible.