Unfortunately, even the busiest spiders spin so little silk that it's nearly impossible for us to make use of it the way we do with the product of silkworms. But anything that's "nearly impossible" is, by definition, possible (though likely very difficult), as demonstrated by a gorgeous golden cape on display at the London’s Victoria and Albert Museum art made entirely out of silk spun by 1.2 million spiders.
The video above is a little melodramatic for my taste, so I recommend turning down the sound and just looking at the pictures of the cape and the artisans at work on it.
I can't even imagine how much a thing like that might be worth, but there are potentially applications of spider silk that may soon be available for much more common and inexpensive applications. At the annual meeting of the American Physical Society that will take place in Boston at the end of February, no less than seven groups will present research about or inspired by spider silk. My favorite is a talk describing a number of electronic applications including transistors, microelectronic wiring, and strain gauges for heart pulse monitoring.
I don't suppose I'll ever have a spider silk shirt, as cool as that would be, but one day I might have a cell phone that runs on spidey power. I think I prefer it that way - gold isn't really my color anyway.