[city41]

I also had the same idea: http://timesliceapp.com That is just a landing page, no product actually exists.

[prawn]

Not so keen on the pop-out box design, but I quite like the general idea. If you want some design help, let me know.

Picturing it shading hours in the office, after-hours appointments, approximate lunch times, reminders to move cars or do other things.

[city41]

Thanks for the offer. I really don't have any plans to pursue this idea, for various reasons. I did this quite a while ago. It ended up being more an experiment in landing pages and google ads.