Imagine being able to run
npm install gprs to add GPRS tracking support to a hardware project... Well, now you can with Tessel!
The idea behind hardware platforms like Tessel is to make it easier for software developers to interface with hardware. This is ideal if you've ever thought it would be nice to hook up a movement sensor to a camera to take a photo whenever your dog or cat moves.
This is why Arduino was such a big deal: it made it easier for programmers and non-technical tinkerers to upload code to a microcontroller using a computer and USB cable.
On the other hand, Tessel has built-in Wi-Fi and an ARM Cortex-M3 microcontroller. Because it's so powerful, it can run thousands of standard Node modules straight from npm. And even better, Tessel has a wide selection of hardware modules, including:
Naturally all of these toys come at a price: Tessel with a single module costs $99. You can also buy Tessel with all available modules for $599.
I have an Espruino, but I don't have a Tessel yet. I like the idea of using
npm install with Tessel, but Espruino is already easy to connect to sensors and other hardware, particularly for those with Arduino experience.
My recommendation is to try Tessel if you're perplexed by hardware but good at Node, and have some free time and cash.