Zango, nee 180solutions, a well-known adware firm which has been accused by the US Federal Government of promoting their business in an unlawful fashion, is shown by Sunbelt, whose CEO has a record (see Google Groups, news.admin.net-abuse.email) of being in favor of (or at the very least, unopposed to) spamming, to have filed a frivolous lawsuit in an attempt to exercise SLAPP (Strategic Litigation Against Public Particiaption) - an act which is itself unlawful in many US States.
The US civil Justice system is deperately in need of reform - the only practical way to stop frivolous lawsuits is to institute an *automatic* "loser pays" system (which must also mean "plaintiff pays if the suit is dropped and not settled"), so that anyone filing suit for the sole purpose of annoying people or causing them expense will be in more danger than his intended victims.
But that won't happen. The current system is too lucrative for the lawyers who make the rules.