A YouTube video claiming that it's possible to cut glass with scissors by placing the glass underwater has been attracting some skepticism. Geekologie suggests that the guy in the video is swapping out pieces of glass with other pieces of glass as he pretends to cut it.
Hmm. I'm no expert on this subject, but after some quick googling, I'm inclined to believe that it is possible to cut glass with scissors by holding the glass underwater.
SpectrumGlass.com, which appears to be a commercial glass company, addresses the claim on their site (though not with specific reference to the YouTube video). They say that the trick does work, though it doesn't make a very clean cut. They quote from Scientific American to explain why holding the glass under water aids the cutting process:
water causes glass to crack more easily because when a water molecule enters the crack, a reaction occurs in which a silicon-oxygen bond at the crack and an oxygen-hydrogen bond in the water are cleaved, creating two hydroxyl groups attached to silicon. As a result, the length of the crack grows by the size of one bond rupture. The water reaction reduces the energy necessary to break the silicon-oxygen bonds, thus the crack grows faster.
An article by some guy name Paul Umstead, titled "How to cut glass without a diamond cutter," also asserts that the glass-under-water trick works. Umstead sounds like he knows what he's talking about, which is more than I can say. So I'm going to say that it seems to be true that you can cut glass with scissors by holding the glass under water. I would test it out myself, but I don't have a spare pane of glass lying around.