I have been using Digital Ocean as a sandbox for playing with Docker, and it has been great. I can spin up a server in less then 1 minute, install the Docker dependencies, and be up in running in no time. I do what I need to do, and then I spin it down if I don't need it anymore.

I wrote down my notes on how to get Docker running on Digital Ocean, if anyone wants to play with it. There is even a promo code for a $10 credit for new signups.

http://kencochrane.net/blog/2013/06/running-docker-on-digita...

I had a couple of issues when I first tried using them, but I was able to get help pretty quickly on a Saturday morning no less. I haven't used them for anything production quality yet, I have most of that stuff on EC2 and Rackspace right now, but I hope to start moving some smaller projects to DO as they come up.

Someone else mentioned this already as well, but the SSD is so nice compared to EC2's EBS, so if you are doing anything with lots of I/O then it is a must have.