I never get stuck in stores because I always have a list with me and don't look at anything except the items written down. In unfamiliar stores I can take a long time simply because I have to find the items, of course.
There are only two things that are sure to get me "un-stuck"; the need for a cigarette and the need to go to the bathroom. Everything else has to wait.
I've been meaning to call my mom since yesterday, but every time I remembered I've just sat down and can't be bothered to reach for my cellphone, which is right next to my laptop. 