I just found out something very cool about the Insight, it has an OEM coolant to oil heater. Apparently, Honda has done this on all their high mileage cars (almost, can't find any use on a Civic HX) like the CRX HF, Civic VX, and yeah the Insight (at least the first few years, sounds like they removed it in 2004). There is a picture I took this morning below. The oil filter screws to the heater, and coolant also flows through the heater. So, as the fluids both flow through hit, they warm/cool each other.
There is more information about these heaters and their importance in a thread Oil Pan started here:
http://ecomodder.com/forum/showthrea...ger-34731.html
Here is a better picture from a different engine:
