S2 CalendarWidget - free (with a donate version available) - great desktop widget that shows your appoingments and gives easy acces to the stock calendar.
Battery Left Widget - free widget that shows remaining battery time and % used.
WeatherBug - great free live local weather with alerts. I use the paid "WeatherBug Elite" version.
I use "CalWidget", which is what the stock Calendar widget should have been. I've put this on my main home screen as a 3x3 widget. If you're using the stock widget, go get CalWidget now. Seriously.
I have also installed "Battery Left", which seems to actually provide a dependable battery reading. Note: The screenshots at Androlib do not do it justice, it's actually very nice to look at.
For weather, I just look out the window.
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