graphing sensor data

What's the value of collecting and logging sensors data if no graphs are produced? (a rhetorical question :)

As with many things, graphs can be generated in very-very many ways. I preferred using RRD until I found an excellent alternative - dygraphs!

Here are some examples of how I've utilized the dygraphs powers:

Electricity consumption measured from the meter directly.

The "idle" consumption is from the inverter-pump, refridgerator, aquarium lighning+pump, home HiFi and couple of connected wall-warts.

The peak comes from coffe-kettle and some breakfast preparations. 

Celler's temperature and humidity measured by a HopeRF TH01.

All three graphs data is gathered by (2) AVR microcontrollers and stored in an old EeePC from Asus running a pure debian Linux. 

Temperature measurements from the my wireless weather-station's outdoor unit.