The poster children of the dotcom boom certainly were - pets.com, webvan, etoys.com (though I can't say with 100% certainty they were all specifically listed on NASDAQ).
It was the IPOs that drove the boom (and subsequent bust). Public investors falling over themselves wanting to get in on the "next big thing". Older generation companies were never going to deliver the kind of quick return multiples that characterized the boom (though as we saw, the enthusiasm certainly jacked up their share prices too, but by and large they managed to ride out the storm).