Weird blue gelatinous balls, about 3cm in diameter, rained on Steve Hornsby, of Dorset, England during a hailstorm last week. He collected them in a jam jar and put them in his refrigerator. From the BBC:
Josie Pegg, an applied science research assistant at Bournemouth University, speculated that the apparently strange phenomena might be "marine invertebrate eggs".
"These have been implicated in previous 'strange goo' incidents," she said. "I'd have thought it's a little early for spawning but I suppose we've had a very mild winter.
"The transmission of eggs on birds' feet is well documented and I guess if a bird was caught out in a storm this could be the cause."