After going through many dog beds trying to find just the 'right' one, I discovered this bed and bought one for each of my girls. The girls are 3.5 and 5.5 pounds and they love, love, love these beds. They are made by Mammoth and are really constructed well. I just drape their fleece blankets on top and they are good to go.
I think they especially love the donut shape because Yorkies love to snuggle and this bed just seems to conform to them.
Check them out at?
http://www.mammothoutlet.com/smallus.htm