I recently built a smaller, indoor system and just thought I would share my findings with the group.
Basic rundown is I am using an induction range in conjunction with a cheap stainless pot in order to heat all the liquid. Since the "burner" is 2.8kw on high or 3.7kw on boost, it is plenty of power to get a full boil 6-7gal to boil vehemently. I created this system because I didn't want to mess with electricity or have a 240v outlet installed somewhere, but I did want to brew inside.
Full details and pictures of the system (it's easier and allows me bigger picture sizes, sorry to make you click a link)
Let me know if you have any questions.