Has anyone tried to using a PIC32-PINGUINO-MICRO as a basis for an energy monitor? @ € 13.00 they seem like an powerful piece of kit. Looking at the spec unless I am reading it wrong, it has two ADC comparators which means you can sample both voltage and current simultaneously at much higher speeds. Also conversions can be done in sleep and idle mode which means low power consumption. It has a SD card slot for logging and a RTCC  (though i think you may need to add a 32768 Hz xtal for that).  The language is similar to that of the Arduino so porting should not be too difficult. The fact it has 256K Flash and 32K ram and a clock of 80Mhz is probably a bit irrelevant but you can never have too much horsepower I suppose. 


I was looking for something with a bit more grunt than the "pro mini" I use at the moment and this seems to fit the bill.