JeeLabs has been working on a new board called JeeNode Zero:
Enter the STM32, the 32-bit ARM series from STMicroelectronics which has been around for several years, with new chip releases at a breathtaking pace. While most of the more advanced chips are only available in 64-, 100-, or even 144-pin packages, there is also an active line of smaller chips in 20- and 32-pin versions. For these, the STM32L series is particularly interesting from a low-power standpoint, with its “stop” and “standby” mode power consumption in the single microamp range, sometimes even lower.
And so the idea was born to try and design a new entry for the JeeNode family, which would again combine a µC with a low-end radio, i.e. the RFM69 successor of the RFM12.
Since there are no DIP versions of the STM32’s, the size can be made considerably smaller than the ATmega-based JeeNode v6. It all ended up being a unit of about 20×40 mm, with all the components on one side, and a large “main header” to support solderless breadboards
Project info at Jeelabs homepage.