You can use netstumbler or vistumbler to find hidden network if you want to find them so as RobertoS says its pointless it adds like 10 seconds to the job for any one who actually wants to find your wifi.
Ash
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Virgin Media 50Mb/s
[IMG]http://speed.io/pics/4107/0447/speed.io.png[/IMG]
2004: Blueyonder 256k/512k => 2006: Blueyonder 2Meg => 2009 Virgin Media 10Meg => 2009/10 Virgin Media 50Meg => 21/04/2011 sky Unlimited
Desktop 1 Intel Core i5 2500 4gig DDr3 1333 64GB SSD 250gig sata 3 HDD 1TB sata 2 HDD Blu-ray RW Nvidia 8800GTS Win 7 Pro
Desktop 2 Intel Atom 330 2gig DDR2 677 250gig sata 2 HDD DVD-RW Win 7 Pro
Desktop 3 AMD Phenom 9500 2gig DDR2 677 500gig Sata2 HDD DVD-RW No specific os (test machine)