WAKE UP! *slap*

I don't ingest any coffee in the morning. Usually the walk to and from my lectures does the trick. Any unusual weather (snow, rain, sleet, etc.) I encounter keeps me alert. The walk is also substantially long, so I use up enough energy to wake up from a mid-morning slump.

If I do wind up dozing off in the middle of a lecture, a sharp pinch wakes me up for long enough. It's less conspicuous than a slap across the face.

Jam it back in, in the dark.