iNetBau PlotManager
PlotManager, PlotConverter and PlotViewer in one program! The iNetBau PlotManager is a program for the output, conversion and viewing of plot files in the HP-GL, HP-GL/2 and HP-RTL formats. The output of plot files is possible even on plotters that don't support the HP-GL protocol! ... In addition, you can send plot files directly to a plotter with this program (regardless whether the plotter is connected by LPT, USB or ethernet). ... The files don't need to be interpreted and will thus be plotted genuine, looking the way they were produced by the user.
http://www.plotmanager.inetbau.de/download/inetbau_plotmanager.exe - 4Mb - Download - Screenshot

CZ Plotter Monitor
CZ Plotter Monitor 3. 0 is a powerful, easy to use print management software that allows architectural and engineering company to easily track and monitor their plotter's printing activity, and recover the printing cost based on total square feet printed. ... Captures the detail print job information including name of the user who send the job, the document name, total square feet printed, total cost, submitted time and date, destination plotter, name of the computer from which the job was sent, color and paper width and paper length.
http://www.czsolution.com/download/CZPlotterMonitor3.zip - 12Mb - Download - Screenshot

SignGo
SignGo signmaking software has everything you need to make professional signs. Create text, shapes and freehand graphics at any size to cut in vinyl. SignGo includes essential sign making tools such as InlineOutline, shadows, scanning, tracing, welding, text on arc, node editor, gradient fills,... Import or paste graphics from your favourite graphics program and use the powerful cutting utility to drive your cutting plotter. ... SignGo is ideal for use by anyone that wants to drive a cutting plotter, signmakers and sign making companies, model makers, graphic designers and hobbyists.
ftp://ftp.signgo.com/pub/sg110p7.exe - 12Mb - Download - Screenshot

SignGo Lite
SignGo Lite signmaking software has everything you need to make professional signs. Create text, shapes and freehand graphics at any size to cut in vinyl. SignGo Lite includes essential sign making tools such as InlineOutline, welding, text on arc and node editor. ... Import or paste graphics from your favourite graphics program and use the powerful cutting utility to drive your cutting plotter. ... SignGo Lite is ideal for use by anyone that wants to drive a cutting plotter, signmakers and sign making companies, model makers, graphic designers and hobbyists.
ftp://ftp.signgo.com/pub/sgl110p5.exe - 9Mb - Download - Screenshot

HPGL Import for AutoCAD
HPGL Import for AutoCAD is a plug-in for AutoCAD 2000, 2000i, 2002 and 2004. This plug-in gives AutoCAD the ability to import geometric data from HPGL Plot (PLT) files. HPGL is the Hewlett Packard Graphics Language designed for specifying 2D graphical information for the HP range of plotters. ... HPGL plot files contain information regarding the movement of the pen of the HP plotter. ... HPGL Import for AutoCAD converts these pen movements into AutoCAD entities and adds them to the contents of the currently opened AutoCAD drawing.
http://www.fpsols.com/installers/HPGLImportAC.exe - 391Kb - Download

HPGL Import for Surfcam
HPGL Import for Surfcam is a plug-in for Surfcam. This plug-in gives Surfcam the ability to import graphical data from HPGL Plot (PLT) files. HPGL is the Hewlett Packard Graphics Language designed for specifying 2D graphical information for the HP range of plotters. ... HPGL plot files contain information regarding the movement of the pen of the HP plotter. ... HPGL Import for Surfcam converts these pen movements into Surfam elements and adds them to the contents of the Surfcam element database.
http://www.fpsols.com/installers/HPGLImportSC.exe - 293Kb - Download

HPGL Import for Rhino
HPGL Import for Rhino is a plug-in for Rhino. This plug-in gives Rhino the ability to import graphical data from HPGL Plot (PLT) files. HPGL is the Hewlett Packard Graphics Language designed for specifying 2D graphical information for the HP range of plotters. ... HPGL plot files contain information regarding the movement of the pen of the HP plotter. ... To import a PLT file select Open from the File menu. ... HPGL Import for Rhino supports plot files created by drivers for the following plotters:  Hewlett-Packard 7475A Hewlett-Packard 7550A Hewlett-Packard 7580B Hewlett-Packard 7585B...
http://www.fpsols.com/installers/HPGLImportRH.exe - 293Kb - Download

HPGL Import for SolidWorks
HPGL Import for SolidWorks is an add-in for SolidWorks. This add-in gives SolidWorks the ability to import graphical data from Hewlett Packard Graphic Language Plot files. HPGL is the Hewlett Packard Graphics Language designed for specifying 2D graphical information for the HP range of plotters. ... HPGL plot files contain information regarding the movement of the pen of the HP plotter. ... To import a HPGL Plot file select Open from the File menu. ... HPGL Import for SolidWorks supports plot files created by drivers for the following plotters:  Hewlett-Packard 7475A Hewlett-Packard 7550A...
http://www.fpsols.com/installers/HPGLImportSW.exe - 293Kb - Download

MathCalc
MathCalc run with the calculator and graph plotter mode. Within the calculator mode, you can compute mathematical expressions, trigonometric, hyperbolic or logarithmic functions. The entered expressions and functions are saved into formula lists. The program has a handy, easy-to-use formula... Within the plotter mode, you can plot 2D graphs a few ways: using tabular data, importing the data from files, pasting data from Windows clipboard or assigning Cartesian (y = f(x)), polar (r = f(u)) or parametric (x = f(u); y = f(u)) functions.
http://www.ypssoft.com/program/matce2_1.zip - 1Mb - Download - Screenshot

ImageDIG
ImageDIG consists of three integrated modules which allow the user to convert 2D flat images into 3D (x,y,z) data or if a graph, convert the graph in image form into 2 dimensional numerical data. The third module is a full analysis plotting utility where the user can import either the 2D or 3D... However, no other program includes an image to 3D numerical data converter and a general purpose x/y plotter. ... Computer generated plots (linear, log, fractional, etc), scanned images from articles for the 2D digitizer, and ascii data files for the universal plotter.
http://www.imagedig.com/download/install.exe - 5b - Download - Screenshot