Always.
Get up, check emails, feed children, walk them to bus stop, chatter with other moms who are also still in thier pajamas, come home, make more cofee, work all day doing this and that. About 3:40, throw jeans and a sweatshirt on, go pick up kids go to the grocery store, come home and put pajamas back on.
I try to put regular clothes on if I am going anywhere in town, but I have been known to go to the lab in my slippers.