I like the flexibility, but you have to be conscious to still set boundaries. Having to leave the office to catch my train on time is a great motivator to make sure everything is wrapped up and I don't linger at the office. When work is at home, what's another 15 minutes, or 30, or 2 hours.. I'm hearing from my coworkers that they are having a hard time with separating at the end of the day, when "going home" is just going into the other room (or disconnecting from the VPN).