VT100 Control Codes  
MUDhalla is a website dedicated to multiplayer text adventure games, also known as MUDs.
The VT100 was a computer terminal made by DEC (Digital Equipment Corporation). It became the de facto standard used by modern terminal emulators.
The VT100 was introduced in August 1978, following its predecessor, the VT52, and communicated with its host system over serial lines using the ASCII character set and control sequences (a.k.a. escape sequences) standardized by ANSI (American National Standards Institute). The VT100 was the first Digital mass-market terminal to incorporate graphic renditions like (blinking, bolding, reverse video, and underlining) as well as a selectable 80 or 132 column display. The VT100 also introduced an additional character set, often called box characters, that allowed the drawing of on-screen forms.
The control sequences used by the VT100 family were largely compatible with the 1979 ANSI X3.64 standard. The ANSI standard was later updated by the 5th edition ECMA-48 standard in 1991, ISO/IEC 6429 in 1992, and ISO-8613-3 in 1995.

VT100 Console Codes

Control Characters
Escape Sequences
CSI Color Sequences
ECMA-48 CSI Sequences

Links

If you want a link added, you can email me at mudclient@gmail.com.

Clients supporting VT100

Comparison of MUD clients - Mudpedia contains a list of MUD clients with VT100 support.
Comparison of terminal emulators - Wikipedia has a list of terminal emulators with VT100 support.

Codebases

Comparison of MUD codebases - Mudpedia contains a list of MUD servers with VT100 support.

Snippets