I havent looked into using HTTP with mail clients in depth, but a few months ago, I was reading how people were using a program that would act as a POP to HTTP protocol converter/proxy... If you google it, you'll find it since its a common question.
There's several ways to monitor CPU and Motherboard temps, but I believe the most common way is to use lm_sensors available at:
http://www2.lm-sensors.nu/~lm78/ I tried to install it on my Slack box from source, but it was giving partially correct data...
Mike