Nice Things from AliExpress
When building your own electronics projects, it's useful to be able to get certain modules and supplies ready made, especially if they're cheaper than you're building your own. Here's a selection of things that I recently got from AliExpress that I think are excellent value.
There's a long and interesting thread at Mikrocontroller.net forums about cheap stuff from China, which I did get a couple of suggestions from.
Unless mentioned otherwise, all items have free shipping.
DC-DC Step Down Converter, 1.5 to 28V, 3A, LM2596, about 0,50€/piece
Works as designed, and can't be beat on price. Adjusting for small voltages is a bit finicky, but definitely works. I'm using this for both 3.3V as well as 5V off 12V or 24V rails.
ESP8266 WiFi Serial module, board ESP-1 with GPIO, about 3€/pience
As of late October 2014, there is a public SDK for the chip, but I have yet to flash my own custom-built firmware into one of them. The forum at http://www.esp8266.com/ has more info.
100 WS2812B LEDs with cap, series resistor, about 0,15€/piece
This board has v-cuts, so you can break the 10mm-diameter boards off. Three pads for in, three for out allow quick soldering of cable to eack LED. The boards include a 100nF cap, and a series resistor on DIN to protect the input.