I was going to say repairing clocks but I'm not now, or I just did so defeated the first sentiment!
As an amateur painter I can totally lose track of everything if I get involved in a fresh canvas or sketches or a combination of these. Once I put the music on and bring out the equipment anything can happen, especially when I attempt abstracts.
It's like I become immersed/lost in the action of mindless doodling and I can forego meals, meetings, anything. The nearest feeling I can compare it to is when a dream ends and you wake up on that cusp between reality and dreamland - disorientated, full of something slightly mysterious, frustrated at having to come back into the real world but relieved because the dream scenario wasn't real after all!