Enjoy stunning effects when the screen dims. From the makers of TV Tube Sleep, SleepFX has been developed in response to overwhelming customer demand for more effects and options. Effects include the famous TV Tube (now with sound), Split Columns, Spin, Fade Tiles, Suck and others. Effects are customisable using options such as effect type, animation speed and sound. 
Available to buy in Cydia for $4.99 from the BigBoss repo.

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Versions on other repos is a trial version that displays the effect up to a maximum of 10 times.