2 - Interface needs to be close to unconscious, visible, and tentative

To make it so the interface to Glancing is almost backgrounded and to encourage perhaps unconscious use, there's a number of tricks we can use:

- it's small, both physically, and how much it stands out among other application. It got a tiny icon and it operates in a very Mac-like way, sitting where these sort of applications usually sit. Looking at the icon and opening the menu is a familiar gesture, so there's a low cognitive overhead in looking at who's online, made even lower by the fact you don't actually choose to glance -- it's a side-effect of seeing the list of who's in your group. And seeing that list is only a single click away from whatever you're doing, because that menu is always available.

- it's slow. The icons are deliberately very similar so that when the glancing activity changes it doesn't immediately catch your attention. If it did, that might mean each person in the group would decide to reciprocate, and suddenly you're all in an encounter situation you didn't want. So the icons are different enough to tell you the activity level, but not different enough to be distracting. Given the fact people might not notice the level for a while, Glancing is a slow application. A glance persists for 2 hours -- that is, two hours after you've done a glance, the eye will still be open a little bit.

- ambiguous. These two contribute to the feeling that you don't know whether people have deliberately opened the menu or not, or whether they've even noticed you've been sending glances. It brings in that 'tentative' aspect I was talking about earlier, hopefully addresses that problem we saw in Montage. Something that adds to this is that you don't glance at a specific person, you glance at the whole group. Just to restate this politeness thing: if you were sitting round a pub table with your mates, you wouldn't just keep on looking at a single person -- that's a subactivity and frowned upon. Besides, everyone else would see you doing it and think you were weird. So to be polite you'd distribute your glances, your little strokes of recognition, around the entire table. What Glancing, the application, does by glancing at the entire group is assume in the first instance you want to be polite and just do that instead.