Here is a list of tools commonly used when dealing with the Eye of the Beholder files:

eob_uncps - Windows based GUI for decompressiong compressed EOB files ( requires 2.0 .net framework )
(based on uncps source - beta with no re-compression and no format 1 compresison handling)
uncps - Decompressor for cps-compressed files.
(Source code for decompressing some of the cps-compressed files, works for all EOB1 files. Doesn't handle format 1 compression)

*NEW* New Uncps tool, early version, creates a bitmap out of CPS files. doesn't handle format 1 compression either :P

Create, open, save and view PAK-files as well as preview of images from PC and Amiga versions. This tool handles both decompression AND compression of all known methods from 0 to 4! Requires .NET framework to run.

unpak - Decompressor for pak-archives files.
(Source code for un-archiving pak files.)

uncps-AGA - Compressor/Decompressor/Viewer for CPS/VCN/VMP compressed files (amiga/PC VGA)
(AMIGA tool v0.9)

WestwoodTool.library Compressor/Decompressor/Viewer AMIGA library for CPS/VCN/VMP formats
(EOB1/EOB2/LandsOfLore's formats supported)

EobViewer - A minimalistic wallset viewer written in Java, including source. Only reads Amiga version EOB1 wallsets.
(Platform independant java-tool)

ADLPlayer - Player for sound and music clips stored in EOB ADL files. (source code; written in (Free)Pascal)

MazeExplorer - 2D Maze explorer showing level 9 (Commodore C64)

Eob2InfReading - Read the data structures stored in EOB2 .inf files. ((Free)Pascal sample source code)

WestPak2 - A file viewer/explorer for old Westwood games (EoB, LoL, Kyrandia, Dune2)

EoB2LevelExplorer - Browse the levels of EOB2 with map and EOB like 3D view.

Script Decompiler - Decompiles the script information from EOB1 inf-files.

Script Decompiler v2 - Decompiles the script information from EOB1 inf-files. It's quite similar to v1 but there are a lot of bug fixes in the parsing and the output is a bit more verbose, like each sub-script top has a reference to the trigger etc. It also adds a simple string compression to the string pool.

BMP Depacker - Depacks EoB3 and Dungeon Hack *.BMP files located in the *.RES and *.GFF files. Source included.

EOB I - WGET (Wall Graphics Extraction Tool)
A simple program for extracting all the wall and wall related graphics from the PC version of the first Eye of the Beholder game.

Java EOB I library - A library in progress used for JackAsser's conversion to C64. It's provided as-is and contains quite alot of more information regarding the formats than is documented on the wiki as for now.

WallsetViewer - A tool written in Java capable of extracting wallset graphics from both Amiga and PC, including the ega-walls (Eye of the Beholder I only). All files that are needed are contained in this archive. All data files have already been uncps'ed and renamed so that they do not collide.