Looking for a winter hat

I'm looking for a hat to wear in the winter, to keep my head warm while going to/from work. I wear business casual to the office, defined as dress pants, shirts, and shoes, with a wool charcoal calf-length overcoat. I am not in a customer-facing role, but routinely am seen by and frequently interact with people much further up the chain from my present rung of the ladder. Therefore, I dress conservatively -- which, incidentally, is also (in my opinion) a prerequisite for the kind of work I do.



I am trying to find a hat that will complement that look and will not make me look like the stereotypical Russian Spy from the old spy thrillers, nor that will be a wool knit cap.



I have never ventured into this particular realm of accessory. Your thoughts are most definitely appreciated! If there is any other information I can provide, please let me know and I will try to provide it.



Thank you!