Are there any other colocation providers where we can do something similar, but not just with a RPi, i.e., send them a small form factor, low-power computer and

Are there any other colocation providers where we can do something similar, but not just with a RPi, i.e., send them a small form factor, low-power computer and a USB stick imaged with (or containing an image file of) an OS that runs well under Xen that we know very well?