By chance* I have discovered that vinegar is a highly effective cure for that stale, dank, stinky smell which permeates my basement from time to time.

*And by chance, I mean, I left a jug of vinegar atop my frontloading washing machine, as I use it as a fabric softener, and during a particularly vigorous spin cycle, the jug fell on the floor and spilled some of its contents. No more stinky basement! It even over-rode the faint odor of the kitty litter.