Targeting could also include demographics, such as male versus female.

FORBES: LivingSocial To Overtake Groupon With $400M: LivingSocial Investor

Chicagotribune.com and The Inquirer (www.philly.com) offer school "report cards" that include scores, demographics and other info.

FORBES: Public Choice

Other features include real-time polling during a conference session, and audience analytics about attendee backgrounds, interests and demographics.

FORBES: Can Topi's Mobile App Make Conferences Social?