You could recirculate water past the CPU via an insulated storage carafe. This would create a fun and exciting gamble wherein you might receive a freshly brewed pot of coffee OR your computer might turn itself off just before the water is hot enough to brew with, and the time it would take would be based on how hard you worked the PC.
Not sure if this is what you mean but an actual heat pump with a compressor could handle this— after all, an air conditioner cools your house to 23C by dumping the waste heat to an environment that can be 40C or more.