Liminality

Feeling in a transitory place these days. Looked up liminal, and when you think about it, a lot of interesting things take place at the cusp: lunar solstice, rites of passage, midnight on New Year's Day, the few seconds before you awake, Schrödinger's Cat, airports, augmented reality:

http://en.wikipedia.org/wiki/Liminality

Taking this to the edge:

In the Mahabharata, Indra promises not to slay Namuci and Vritra with anything wet or dry, nor in the day or in the night, but instead kills them at dusk with foam.