MacNosy
Is a Mac application that disassembles the Macintosh ROM or any 68K or PowerPC codes, by Jasik Designs.

IDA Pro
The multi-processor, multi-OS, interactive disassembler, by DataRescue.

Universal Cross Disassembler
XDASM - DOS based cross-disassembler supports numerous processor types, by Data Sync Engineering.

The Decompilation page
This is the Wiki version of the Decompilation page (originally by Frans Faase, then Cristina Cifuentes). Feel free to keep this page up to date; anyone can edit.

This96
80196 disassembler by zartoven.

palmdeMON
A win32-based disassembler and resource viewer for Palm Pilot applications. Links to other Palm tools.

Misosys Disassembler
Tim Mann's TRS-80 Page includes Misosys Disassembler, aka PRO-DUCE.

High Level Assembler and Toolkit (HLASM)
System/390 assembler toolkit for MVS & VM & VSE (HLASM) including disassembler, by IBM.

The dcc Decompiler
It decompiles small .exe files from the (i286, DOS) platform to C programs.

DASM1600
An Intellivision Disassembler by Frank Palazzolo.

the bastard disassembler
*NIX disassembler. Written in C on Linux for x86 ELF files; intended to support multiple CPUs, OSes, and file formats. Scriptable.

DISA
An OS/2 disassembler for OS/2 device drivers, by Abbotsbury Software.

Application-specific Decompilers
Catalog of decompilers.

MELPS7700 Disassembler
By H.Kashima.

SST Global-Decompilers
Decompilers for IBM midrange systems.

DSP5600x
A 5600x disassembler by Miloslaw Smyk.

AVATAR
A disassembler/patcher/code-explorer for PA-RISC based HP-UX systems, by Allegro Consultants, Inc.

The Decompilation Page
Decompilers, resources, and history.

Re39
Interactive Disassembler for Rockwell C29/C39 (C40) code by Lewin A.R.W. Edwards.

Transputer disassembler.
By Andy Rabagliati.

SSEM
The World's First Stored Program Computer - disassembler included.

FARGDIS
Fargo Disassembler for TI-92 DOS versioin, by John Grafton.

TRACE32
Microprocessor Development Tools include multi processor emulators and disassemblers.

Reverse Engineering Compiler
Program that tries to make source coden (C) from binary, multiplatform. There are MIPS disassembler too, by Giampiero Caprino.

PICE/WIN
Panasonic MN1500 Emulator Interface for Windows includes Disassembler for MN1500 by TransferTech.