My colleague with the office next to mine is on parental leave but brings her baby to the office most days to work. She says it's a way for her to escape her 3 year old, who really makes work impossible!
A former student of mine (from Hungary) wrote an article about attending conferences with her baby, giving 22 talks in the first two years! Here's the link.
. It sounds pretty crazy to me, so I'm not exactly recommending it.