Pre-production basic questions for electricity/energy generation

Well, it's nice to find a new forum out there where I can hope my voice won't get lost in the crowd.  

I've long been intrigued by the potential of Stirling engines and have some cheap project toys here at home. I'm a handy guy but I don't have a machine shop.

Here's my quick question for today:
Over the past year I needed to replace my NG fired furnace and that room it's in gets way hot. Although a fan isn't required for the BTU output I've got I may need to install

one at some point just to cool the room off. Anyhow, this got me thinking...

Is there any way I could either (a) attach a Stirling generator to capture some of that heat off the boiler or flue or could I (b) place some sort of Stirling generator on top of my metal chimney cap (or replace it all-together) with some sort of Stirling engine that could capture the heat and convert to electricity?

The chimney could be optimal b/c the furnace will run often in the winter and the outside ambient temperature is cold out.  32deg F or below to a flue temp of 100deg F + would be a pretty good difference to work with.

Thoughts anyone???