The UNO R4 WiFi features Wi-Fi and Bluetooth Low Energy connectivity, while the UNO R4 Minima provides a cost-effective option for those seeking the new microcontroller without additional features.

Microduino: An Arduino clone nearly as small as a quarter, for $20 Arduino Uno capabilities divided into two small boards for extreme portability.

For beginners learning to program Arduinos, a web-based, fully networked developer environment called Codebender could drastically reduce the learning curve.

While you can get an Uno clone for around $10, the Arduino 101 will retail for around $30 USD which isn't bad at all considering it has a built in Bluetooth radio, accelerometer, and gyro.