I've always wanted to find a better way to sell my prints online. Traditionally I would wait until someone bought a print on my website, then purchase a copy from my printer, receive it, repackage it, then mail it to my customer. Although that process is great for seeing the prints first, it's not so great when you don't have a lot of time to invest in the process.
I searched online for possible drop shipping solutions and came across the Pixpa / WHCC integration. With Pixpa, you can build an awesome online portfolio / website. WHCC (White House Custom Color) is quite possibly one of the best online print labs. The two have a great integration where you can setup prints and pricing on your website and then make a completely automated process.
To make things a little simpler, I have made an in depth video on YouTube showing all the steps involved and giving you some tips to make this a successful process for yourself.