Today, at work, I noticed an unannounced guest in the building:
Just going by the twin cerci at the tail end of this critter, and our site's proximity to water, that this is a mayfly, specifically a not-quite-adult subimago. Since mayflies are basically the prime example of extremely ephemeral creatures, doomed to die after the briefest of existences, I didn't want to see this doomed creature's existence to be wasted indoors, alone:
The insect needed little coaxing, one quick flutter of the hand and it took off to join the mating swarms over the site's pond. It's bad enough when a long-lived creature is cooped up inside all day, for a creature with a lifespan of mere hours, it's intolerable.