A few days ago ThingM friend Rusty, operator of the wonderful SomaFM, wondered if there would ever be a "blink(16)": a blink(1) with a 4x4 grid of LEDs. Well it turns out that due to a secret feature of all blink(1) mk2s, it's actually pretty easy to make, if you have some WS2812-style LED strip laying around.
Making a blink(1) mk2 use 16 extra LEDs is pretty easy because it has a hidden 3-pin port for wiring up WS2812/NeoPixel-type LED strips. In this photo, you can see the three holes: one each for Gnd, +5V, and data.
Below is a video showing it in action. The two 'blink1-tool' commands used in the video are:
blink1-tool --random=1000 -l 18 -m 50 -t 50 blink1-tool --running -l 18 -m 200 -t 200
Notice the "-l" option. Using this option, you can control a single LED in a blink(1) mk2. For instance, on a regular blink(1) mk2, you can do:
blink1-tool -l 1 --red blink1-tool -l 2 --blue
to make the top LED red and the bottom one blue. For the "random" and "running" commands, the "-l" option means how many LEDs to use.