Shipping Charges

I want to move the project, so I've ordered more bits and pieces today.

First, since it doesn't look as if the tablet can be convinced to act in host mode, I need a USB host-capable kitchen node. There's a great new device out that could do this very well, and very cheaply - the Raspberry Pi has USB host, SPI, I2C and GPIO ports enough for what I need. But it looks as if even existing orders won't be fulfilled before April, current ones much later. I don't want to wait (though I might order one anyway). I can't use USB host shields (the SPI bus is needed for the wireless), so the only option is the Arduino Mega ADK. Overkill for what I need (with over 50 digital and 16 analog ports) expensive (certainly compared to a jeenode or a Pi, and even the tablet), and I still have to add an RMF21B wireless board; but it's a way forward. That's coming from the only UK shop I could find that actually has one in stock.

Then there's the wireless module, that comes from Jeelabs (as Seeed never did do the breakout board) in Holland.

I need some water flow sensors (also Seeed Studio) but the only place that has the 3/4 inch version that fits our heating circuit is a place in France.

And finally yet another (UK) place for some basic wires, resistors, LEDs, plugs etc.

I feel like I am paying more on postage than on parts...