October 19, 2007 Radar Networks has been flying under the radar for a few years now, but on Friday the startup's mastermind, Nova Spivack, unveils its first product, a brainy social network called Twine. Twine is a digital data dump with structure – what Spivack calls (what else?) a “semantic graph.” As with Facebook or MySpace, members get their own home pages, through which they can connect with