Opensource single board computers.
Which one have your eye? or eyes

pi zero for being a cheap ass device you can control remotely.

Wild i hear data centers are even accepting co location, could be cool to host one something headless for when your on a public wifi or whatever purpose you may have for it. a cool data center would be prq dunno who else.

There are very few datacenters that accept colocation for non-standard hardware at a cheap price. Run a cluster of Pi2 myself.