Last night I broke my lack of sleep jinx, drifting off at the incredibly early time of 1am.
Not long after,
It took me a moment to understand what was going on. The blue flashing, powerful enough to light up the room, was coming from the LED on the laptop's wireless card. The machine seemed to have spontaneously started up, as PCs in this flat often do, and the card was responsible for the fireworks display.
I went over to eject it from its slot and then crawled back into bed, thinking “I'll never get back to sleep”. That was the last thing I knew until 11am today.