Patagonia’s micro puff vest is probably one of the most useful pieces of clothing I own.  Despite being fairly lightweight, it’s does a great job at keeping warmth in and it’s suitable to wear year-round.  Best yet is that it’s also very easy to pack down and stow away.  See more images on Patagonia’s site: http://www.patagonia.com/web/us/product/mens-micro-puff-vest-alpine?slc=en_US&sct=US&p=83996-0-763

Patagonia Micro Puff Vest

Patagonia Micro Puff Vest