Northern Tool offers the SolarSheat 1000GS Solar Fan Assembly for $899.99. Plus, coupon code "255178" grabs a $100 Northern Tool gift card. With $65.49 for shipping, and assuming you'll use the gift card, that's tied with last month's mention, $500 off list and the lowest price we could find. It features a 1,000-watt solar thermal air collector, duct kit, wall mounts, thermostat, and fan assembly with 15-watt PV panel.