Brollies.

[Kay]

Why is considered unluck to open an umbrella indoors,even when buying one?

[Quizmonster]

As with most superstitions, you are unlikely to find a definitive reason for the 'unlucky umbrella indoors' one. There are some who claim it dates back to a time of sun-worshipping in roofless temples. Clearly, if you raised your parasol, you were denying yourself the sun's blessing and fellow worshippers no doubt beat the living heck out of you...so now we don't do it!

Highly improbable, I know, but no less likely than any other theory you might be presented with here.

[BlueRoom]

Because you might knock something off the mantlepiece!

[cheyenne]

what happened to those see-through ones from the sixties?now they were a good idea.brilliant answer by the way quizmonster!!

[Quizmonster]

Yes, Vinny, I haven't spotted a see-through one...brolly, that is...for  long time. You'll obviously remember Pac-a-macs, too. I once did a Google search for one of those and was horrified by the sites I was offered...all I wanted was a bless�d raincoat! Cheers

[jocook17]

They sell see-through ones in john lewis's for 10 pounds