Free medical billing software for linux

Jbilling is a recurring billing system, targeting companies that periodically charge their customers for services. It calculates and generates the invoices, handles automatic payment processing with credit cards and notifies the customers about the status of their accounts.
It is web-based, once it is installed in a single server, it can be accessed with a web-browser from any computer in network with the server. If the server is connected to the internet, then the billing system is accessible from any computer connected to the internet.
Enhancements:
- The release notes are in the document release_notes.pdf, which is located in the root directory of the binary distribution (jbilling-1_0_8.zip)

Medical Imaging Interaction Toolkit (MITK) is currently under active development, and aims at supporting the development of leading-edge medical imaging software with a high degree of interaction. It combines vtk, itk and the pic-based-libraries of the Div.
Main features:
- multiple, consistent views on the same data. For example, when you have three orthogonal 2D-views and a 3D view and data consisting of a green surface, the surface will be visible and green in all views (as contour lines in 2D, as a surface in 3D), and when you move the surface, it will move in all views. When you try to realize this with basic vtk, you will need to coordinate the position/orientation/color/... of all the views somewhere in your program - exactly this can mitk do for you.
- interactions that create and/or modify data (not only actors as in basic vtk)
- complex interactions with multiple states, e.g., for interaction with active contours
- undo/redo of interactions
- organization of data objects in a tree at run-time, e.g., to represent logical dependencies (e.g., a heart cavity is a part of the heart) or to control the rendering process
- additional properties of arbitrary type can be assigned to data objects contained in the data tree
- visualization and interaction with 3D+t data (basic vtk can handle only 3D data and itk is not for visualization and interaction)
- although mitk is mainly a toolkit and not an application, it offers some support on the application-level, e.g, for structured combination of modules (so-called functionalities), e.g., for combining and switching between one functionality for segmentation and another for registration.
Enhancements:
- New functionalities: IsoSurface, ViewInitialization and Measurement.
- Support for ITK 2.4-2.8, VTK 4.4 and 5.0.
- Lots of bugfixes and improvements, e.g. interaction for rotatable slices.

Billing Software project allows your business to track invoicing and allows your customers to view their invoices online and easily export them to Excel for saving or printing.
Invoices can also be emailed to customers right from the online application for convenience and efficiency.
Enhancements:
- This release fixes some minor bugs in the XML portions of the library files.

Homemade Dictionary is a customizable and easy to use dictionary, with features including background music support.
Homemade Dictionary has a built in "Test Your Word Power Game", a medical dictionary, and a nice GUI.
The dictionary has an initial database of of around 5600 words, including slang. You can add your personal words on the fly. It is very small in size (only 637 KB).
Enhancements:
- Wordlist has been updated

OpenClinic project is a easy to use, open source, medical records system.
It has been mainly developed for private clinics, surgeries, and private doctors.
It is platform independent and has a multi-language architecture.
Main features:
- Environment: Web Environment
- Intended Audience: Education, Healthcare industry
- License: GNU General Public License (GPL)
- Natural Language: English, Spanish, Bulgarian
- Operating System: OS Independent
- Programming Language: PHP
- Topic: Dynamic Content

Printbill is a sophistocated Unix print billing and/or accounting system with associated administration utilities. It primarily supports LPRng but now has limited CUPS support as well.
A simple print filter and accompanying daemon perform pre-printing billing, post-printing billing, print-accounting and print job quote generation. In addition, various utilities for administrators and users are provided - including programs to check your print quota and usage patterns, a web interface for both users and administrators and a command-line quote generator.
Charge rates may be specified on per-page, per-percent-coverage or both, and any number of printers/print queues can be provided (with different charge rates and printer parameters). Monochrome and CMYK colour printers are supported (with separate charge rates for both colour and black ink).
For all filters, processing can happen out-of-order, and you may prioritise jobs on the basis of size (jobs larger than a threshold can get lower priority or higher priority as desired) and jobs are billed in parallel / overlapping - jobs which finish billing first get printed first.
This is not necessarily the same as the order of arrival. Detailed stats are collected on a per-printer basis for job size, CPU time for each job, page count and ink/toner coverage, so you can analyse the usage patterns for your printers and predict when a cartridge will need to be replaced. It supports an optional user-supplied anything-to-postscript filter, so you can get properly billed for plain text, DVI files, image files, and so forth as well as PostScript.
Databases and configuration files may be stored on a centralised web server. This allows read-only access so that Unix (and conceivably Windows) clients could easily check quota, calculate quotes etc. remotely.
For fun, an additional filter is provided which allows users to deduct fixed amounts from their accounts (we use it to let students buy drinks and food from an unsecured laboratory fridge).
Enhancements:
- Finished support for per-user per-printer stats, tested that it works.

FreeMED is a Web-based medical records (EMR) and patient management system with a printing system, patient scheduling, an HL7 interface, a billing system, XML-RPC Web services, and many other features.
FreeMED has an extensible modular architecture, allowing it to be customized based on individual practices without having to rewrite core components of the system. It is HIPAA compliant.
Enhancements:
- NPI support (used with newer version of REMITT), initial superbill support, enhanced billing logic and better billing behavior, a DHTML viewer for Djvu documents, additional community documentation from freemed.info, many bugfixes, and incremental module improvements.