I was thinking about something to show weather around you while driving. I guess it should be a fast thing, like the mood, and when you disconnect, it could generate something like a report...
Follow my Idea: I'm driving a route, and it begins to rain. I change my "weather mood" to "raining". Someone behind me sees my avatar with a rain icon, and knows that where I am, it's raining. Then, I arrive at my destination, and turn off waze (it's still raining). Some other user connects, and sees that where I arrived, let's say 20 minutes ago, there's a report saying it's raining. Someone else could comment the report saying whether it's still raining or not, and keep the report alive. That user could then decide to change road, or keep going, seeing the weather icon on users on different roads. The report should be active for an hour at last, just to avoid too many reports.
That's my "insane" idea, if someone has something to add... Please say it!