These kinds of tweaks appear to be hugely popular among jailbreakers. f.lux, for example, is a nice little utility that allows you to add warmth to your display with certain dimming effects, and these can be tuned to operate in sync with the time of day. With a similar aim, Eclipse takes the bright colors of the stock iOS UI and replaces them with darker colors, bringing a night-time, eclipse-like effect.
It costs 99 cents, but whether you prefer the darker look or have simply grown a little bored of the stock set up, this is one of the more conspicuous theming tweaks you’re likely to find in Cydia.
Here’s some screenshots:
Download it, give it a whirl, and be sure to leave your thoughts and opinions via the usual mediums below!