The chill factor.

Here's a brainteaser: Sunny day = cold office.

How? Well, it's April, so unless you're in the direct sunlight, the air isn't all that warm. My house faces south, and the living room is at the front. Therefore it's flooded with sunlight, and on sunny spring days like today, it's quite warm even with the heating off. My office however is on the other side of the house, and gets no sunlight at any time of day, any time of year. Without heating it is, therefore, freezing. I switched on my computer this morning, and before it had even booted up I was too cold to spend any more time in here. Went into my bedroom next door, and it was several degrees warmer.

The solution? Well, I suppose I'll just have to go back to bed until summer...