I was home three days a week with our youngest while starting a consultancy, and I got pretty much all my coding done with him sleeping on my chest, me crouched over him in the couch typing away on my MBP :)

Clients had no idea how delicately I was hitting the keys when writing their code. Deadlines could be missed if he didn't sleep as expected.

As soon as he woke up it was back to being a full time dad. I like to believe that I'm way more productive now since I've become a father - being a parent that's also part of the workforce requires both discipline and creativity.