And now, the Weather Log! No, it's not a record of the weather but it will tell you, with no cost whatsoever, what the weather is.
You can even make your own! Take a log (any type of wood will do) about 5" x 1" (in this case, size matters only slightly) and attach a chain to it. Suspend the log from a suitable support and place it outside.
Here's how it works (and those who are not mathematically inclined may have trouble):
1. If there is a shadow under the log, it is sunny. (No shadow means that it's cloudy.)
2. If the log is wet, it's raining.
3. If the log is swaying, it's windy.
4. If the log turns white, it's snowing.
You will undoubtedly find many more ways to use this wonderful invention. And, like Ikea's Tooltool, the battery remains at full charge.
If you don't want to build your own, I can sell you one for a mere $100. That sounds like a lot but it's actually inexpensive when you consider that you will be on the cutting edge of advanced technology.