If you're using the analogue inputs on your Arduino to measure various signals but would like a greater resolution, that is you need more range than 0~1023 - then you'll need a better analogue-to-digital converter IC. There's many to choose from, however John from tronixstuff has published a new tutorial that explains how to use the Texas Instruments ADS1110 16-bit ADC with the Arduino platform. Doing so is quite easy as the ADS1110 interfaces via the I2C bus, and it offers almost twice the resolution as the onboard ADCs.
Furthermore you can also make differential measurements which aren't possible with the Arduino by itself. There's much to learn, and it's an interesting and possibly useful extension of data gathering for an Arduino - so visit the tutorial to get started. And for more, we're on twitter and Google+, so follow us for news and product updates as well.
When your projects outgrow the normal Arduino-compatible boards, running out of program and flash memory space, or you're stacking on Ethernet and microSD shields, or all at once - it's time to upgrade to the Freetronics EtherMega:
Quite simple the EtherMega is the fully-loaded Arduino-compatible board on the market today. Apart from being completely Arduino Mega2560-compatible, it includes full Ethernet interface, a microSD card socket, full USB interface, optional Power-over-Ethernet support and still has a circuit prototyping area with extra I2C interface pins. So if your project is breaking the limits, upgrade to the EtherMega today.