This TechCrunch article talks about two people facing jail time in Illinois for recording conversations: Using Your Blackberry In Illinois Could Send You To Prison. Florida is one of the 12 states where recording a conversation without permission is a felony although not for a first offense for non-commercial purposes. Fla. Stat. sec. 934.03
Clients will sometimes try to bolster a case by recording an opposing party. This not only exposes them to potential criminal liability, but is generally useless. An unlawfully recorded conversation is not admissible in court.
Here is a much more detailed blog post by a criminal defense attorney: Recording Telephone Conversations and Communications in Florida