The HAD.io parts list section in a project is a great feature, but not very useful for other than a vague idea of what constitutes the project.

I think the parts list would benefit a lot from pictures next to the parts, a reference code, link, price, quantity... The form factor of the parts I chose for the IPM is rather important, as others types might not fit on the perfboard just as well.

I like sourcing my parts from eBay, partly because it's absurdly cheap and also because during the 1-month delivery period I forget what I ordered, then when something arrives I'm happily surprised to find something in my mailbox (thus my sail mail notifier).

Here's proper parts list with pictures, references, the lowest listing price and links to them in no particular order, every part is only needed once:

Picture	Reference	Link	Price
	AMS1117-3.3 LDO This lowers the 5V input to 3.3V for the ESP8266	eBay	$1
	Button (through hole) To put the ESP into programming mode	eBay	$1
	ESP8266-12E with breakout board The heart of the system	eBay	$3
	Right angle, male pin headers (single row) For programming and attaching the light sensor	eBay	$1.5
	Female pin headers (single row) To connect the light sensor to the board	eBay	$1
	Light sensor To read the LED blinks on the power meter	eBay	$1
	0.96" OLED display (I2C) To display stuff	eBay	$6
	Perfboard/prototype board To connect everything together	eBay	$2
	FTDI programmer (5V/3.3V, settable via a jumper) To program the ESP	eBay	$2
	Mini SD card reader module for micro SD card (SPI) To save data on the SD card	eBay	$1
	Micro SD memory card To hold the data, anything above 16MB is good	eBay	$1
	Jumper cables To connect the programmer to the ESP	eBay	$1
	10kOhm through-hole resistor To pull-up the button signal	eBay	$1
	USB cable Doesn't matter which type, it's going to be broken anyway	eBay	$1
	14 parts	Total	$23.5

Some bits and pieces like wire and solder are also needed, I expect any self respecting tinkerer/hacker to have them or break the nearest appliance to get some.

If you don't like eBay then there are other places you can buy cheap electronics from, such as DealExtreme, AliExpress, Elecrow to name a few.