Here are some useful tools which you can install for free thanks mainly to the efforts of the open source community.
Productivity:
OpenOffice.org - Can happily open Microsoft Office filetypes and it also supports open document standards to help future proof your files.
SugarCRM - Customer Relationship Management system. Helps you to make the most of your customer base. This application is web based, so contact Grapevine IT to discuss hosting.
Notepad2 - Notepad2 is intended to be a replacement for the Notepad program that is included as part of Windows.
Dia - Dia is a program to draw diagrams. It currently has special objects to help draw entity relationship diagrams, UML diagrams, flowcharts, network diagrams, and many other diagrams.
Internet Tools:
Firefox - The best Web browser, ever.
Thunderbird - A very nice Email Client, from Mozilla
Gaim - Gaim is an instant messenger (IM) client. Use it to chat with others in real time using any supported network, including AIM, ICQ, MSN Messenger, Yahoo!, IRC, Jabber, Gadu-Gadu, and Zephyr.
Filezilla - This is a very functional ftp client. Useful when you need to move files around on the Internet.
PDF Creators:
OpenOffice.org - has a great pdf export function, which fully supports embedding fonts
PDFCreator - Use PDFCreator to generate PDF documents directly from any Windows program
CutePDF - Create professional quality PDF files from almost any printable document.
PDF995 - Pdf995 makes it easy and affordable to create professional-quality documents in the popular PDF file format.
Graphics & Design:
GNU Image Manipulation Program (GIMP) - It is a powerful and comprehensive imaging solution, suitable for those wanting to manipulate digital photographs, design and export graphics for the web, convert from one file format to another and even produce complex high-resolution compositions for print. This software is just as feature rich as Photoshop.
Gimpshop - Gimp, but setup to copy the behaviour and feel of Photoshop.
Multimedia:
Audacity - Is a sound editing program which can record, playback, and mix sounds or apply effects using a variety of filters. Edit your sounds using Cut, Copy and Paste (with unlimited Undo) and mix multiple tracks together.
MPUI & MPlayer - A great media player with a clean and simple interface. Supports MPEG-1, -2 and -4 (DivX), H.264, MP3, Ogg Vorbis and AAC to name just a few.
CDburnerXPpro - Free, full featured CD burning software for Windows.
Celestia - Celestia is a simulation of the entire universe, based on current astronomical information.