#4 Scribus:
Developed by the Scribus team, Scribus is an open source tool mainly developed for creating and editing PDF documents and desktop publishing. The software competes with major players such as Adobe PageMaker, PagePlus, QuarkXPress and Adobe InDesign. Scribus is designed for layout prepartion, typesetting and for image setting. The software is also used for creating interactive PDF presentations and forms.

Scribus is available across all major platforms such as Windows, Mac OS and Linux.

#5 GnuCash:
GnuCash is a free, open source accounting software, developed primarily for small businesses. The software comprises of double-entry bookkeeping system, with associated features such as checking, savings, stocks, assets and expenses. For small businesses, the software provides extra features such as scheduled transactions, transaction matching, financial calculations and importing. A part of GNU project, GnuCash runs on various UNIX platforms such as Linux, OpenBSD, FreeBSD, Solaris, Mac OS X and more.

Also Read: Watch Out For these 20 Super-Cool Cloud Services

Also Read: Top 10 Internet Service Providers