Use particle cloud with an arbitrary device

I wonder if its possible to register an arbitrary device to the cloud, meaning that I could bascially use any device I want to be able to communicate with the particle cloud?

I really like the cloud but I would love to have my own devices on the cloud

They’ll have to use the correct protocols to be able to connect to the cloud. Then you’ve also got to figure out how to get the firmware to compile for your specific device, since that’s normally done in the cloud.
Then you’ve got to talk to Particle for the Cloud fee, since that’s normally included with their boards, and obviously not if you bring your own. I believe it’s a small one time fee, but you’d better mail them for exact details on that.

Out of interest, what devices would you like to use, and why?