who had taken the seat before me in the bus? Has that person smeared his sweat 'etc' on the seat? which is the cleanest part of the pillar in the bus I can hold on to?

wear the germ viewer glass to know it! it throws a UV light or whatever, to reveal the truth

a purple patch means its sweat, a green patch says its saliva...so on.
-- ravi kris334, Jul 18 2013

Muppet labs version http://www.youtube....watch?v=EFebGZ7FJQQ
[not_morrison_rm, Jul 18 2013]

Invader Zim version http://www.youtube....watch?v=Ryi0XwLFC4g
[spidermother, Jul 18 2013]

Excellent idea apart from the not working bit. UV light won't reveal normal levels of contaminants, alas, unless you spray everything with the relevant stains first.
-- MaxwellBuchanan, Jul 18 2013


Really a germ colony viewer, not individual portraits.
-- popbottle, Jul 18 2013


Great Muppet link [n_m_rm]!
-- xandram, Jul 18 2013


So market the device with a multi-chambered relevant stains sprayer free!. That way you can bend over the empty subway seat and spray it before shining your UV goggles at it.
-- pocmloc, Jul 18 2013


Since it the same stuff in urine, saliva, blood and semen - phosphorous - that fluoresces under UV light. So I'd guess a simple UV light wouldn't be enought - you'd have to do some tricky stuff, spectrometers and a heads up computer display - to get different colors for different kinds of spludge.

Actually seeing germs would be pretty tricky. To get them to fluoresce or glow, you've gotta chemically bind florescent proteins and the like to them. Getting just specific germs rather than practically everything to fluoresce might take some sort of gene tagging tech.

Sounds cool, but hard, to me.
-- CraigD, Jul 25 2013



random, halfbakery