Examples:

FLASHTERM Flashterm is an ANSI capable telnet terminal for the web written for the Adobe Flash Player plugin.
www.flashterm.com

ANSI VIEWER This viewer simulates 80x25 line scrolling. It can display any online ANSI file. There is an address bar at the bottom that can launch other files, or you could direct link into it by adding a "file" URL parameter.

sixteen colors by tainted
Center by zeroVision
Pharcyde by h7
blocktronics logo (b7) by avg
Scum by Noches & zeroVision