DEdit is a DATA fork editor.  

DumpTRUCK! was a batch URL submission tool for most popular search engines in the early 2000's.  It's costumizable so the user could make new search engine submission templates and choose on which ones the submitted URL would be fetched...

Diccionario is a quick lookup translation dictionary from/to Deutsch, Portugès, Français, Castellano, Català, Italiano, English.  

Dynamo is an animation environment that allowed a mid-80's Macintosh user to create vectorial animation, quite easily, using arbitrary points and joints translation by clicking and draging the mouse. This is the demo version.  If anybody...

DesignerDraw is a free application to design and print all sorts of diagrams and charts. Note that DesignerDraw 4.x REQUIRES an attached printer.  

DesignCAD is a CAD/3D builder/renderer that allows you to create 3D blueprints of structures and plans for just about anything you want.  DesignCAD 3.0 also lets you render as shaded 3D surfaces and even Phong shading, which was kind of great...

Data Recovery Tookit 2.0 is a set of tools for the 90's Macintoshes.  It lets you scan and repair volumes, unerase files, protect your drives with system extensions that keep a shadow copy of system files and protects against accidental...

Dragon Burn is an alternative to Toast.  Dragon Burn lets you author CD-R and CD-RW media, copy CD's, backup Mac volumes, extract audio tracks from existing discs to AIFF, CDDA, MP3 and WAV file formats, create audio CD's and even use...

DrDJ is a very simplistic sound mixing application.  It lets you play and cross fade tracks automatically.  It lets you adjust both tracks volume independantly and queue up to 20 tracks.