According to my Mayhem Log I've been on here for 33 days, although I shut down my PC at least once a day.
Yes, I have Mayhem open most of the time when I'm in the Shipyard. Whenever glue or paint is drying, or I just need to come up for air, I read the posts, do a bit of research, a bit of online shopping, then back to the build.
I could watch TV in the other room, but that seems permanently locked onto Forensic Dramas.