is there a way to make my wifi card in my computer to have greater range
What kind of card do you have? I used a linksys wireless card once i think it was model wmp54x something like that. But it had very good reception.
It's illegal to use get "free internet" from someone else. It's called stealing. Nice one.
lol i found out the hard way when i got the cops called on me for "wardriving"
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Also if you are familiar with linux there is a way to make a boot cd that "attacks" secured wireless networks and decrypts the passwords. unfortunatly i cant tell you that because thats probably against the rules of this site