This is one of those ideas, that sounds great on principal, but fails quickly when you think about the logistics. The reason we have data centers in the first place is for convenience, security and backup. Distributing this around peoples homes just for some heat, is ridiculous.
Placing cloud servers in individual homes, and turning them into heating systems. Your house will serve as a data center for companies that depend on cloud computing
via Your next heat source could come from a server, if Nerdalize has its way