Dave Wheeler posted an interesting article about using lots of scale 
hives to monitor the environment.

http://earthobservatory.nasa.gov/Study/Bees/bees4.html

I would love to have a scale hive but never could locate one.  I tried 
eBay and the only thing that looked interesting
was a 330lb platform scale meant to be used indoors ($65).
Try eBay with a search for "platform scale"  Now my question is do you 
think if such a scale were
wrapped in plastic it would survive under a bee hive?

Also while I am not an expert in stain gauges it just seems like if a
company can produce an electronic bathroom scale for under $20 why
couldn't someone put together a kit of say four strain gauges that you 
could hook
up a volt ohm meter and  get a weight reading.  Perhaps the owner would have
to calibrate the kit, and maybe even take a temperature reading to 
adjust for temperature.
With the calibration charts you could get a weight reading.  If anyone  
is skilled in the art
of strain gauges, I would love to see some sort of  cheap design worked 
up.  It only needs
to be precise to the pound and absolute accuracy is not important.

- Dave

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