Considering I've just polished off half a jar of jam, you could say I'm a fan of all things preserved. But inedible LED jams? JellyLamps' bright hues make me sad I can't slather a knife-full on a bit of crust.
When turned upside down, the LED light inside each jar of JellyLamps jam switches on, and glows neon. When flipped over, rightside-up, it looks just like a normal jar of jam—albeit, one that's made from fruit plucked from the bushes of Chernobyl.
Unfortunately they're very pricey for what they are. Each jar runs off two AAA batteries (which casts 50hrs of light, apparently), and costs 35 Euros (around $46). [JellyLamps via HolyCool via OhGizmo]