What could be more practical than light bulbs for cuff-links? One pair glows in the dark and is cheap, while the other is LED powered.

£10.00 London Glow in the Dark Cuff-Links: I am not sure how brightly these glow, but they look retro chic enough to warrant wearing.

$27.99 Amazon LED Cuff-Links: no one has reviewed this set yet; would you like to be the first?

For all manners of strange and interesting cuff-links and other accoutrements, take a gander at 1st Choice CuffLinks and Cufflinks Depot.