Broadcatch is a word coined by Fen Labalme in 1983. The term was also independently used by Stewart Brand in his 1987 book The Media Lab.
To understand the concept described by this term, first take a look at traditional broadcast media (such as radio, TV, magazines and newspapers) and note that they generally consist of a one publisher to many consumers flow of information, and as such rely upon common opinions and beliefs, as each published issue is targeted for a mass audience.
On the other hand, Broadcatch connotes a many to one gathering of information, using a network of personalized agents to ideally sift through all available information and return just that which is of possible current interest from trusted, authenticatable sources and in a form and style amenable to the user. Broadcatch is designed to thrive in a diversity of opinions and provide a mechanism that effectively automates word of mouth.
As this system will learn much about its user (via an incrementally refined personal profile), strong cryptographic techniques are employed to protect one's privacy and allow free access to the world of information without fear of discovery or reprisal.