Securimage is an open-source free PHP CAPTCHA script for generating complex images and CAPTCHA codes to protect forms from spam and abuse. It can be easily added into existing forms on your website to provide protection from spam bots. It can run on most any webserver as long as you have PHP installed, and GD support within PHP. Securimage does everything from generating the CAPTCHA images to validating the typed code. Audible codes can be streamed to the browser with Flash for the vision impaired.

Features

• Show an image in just 3 lines of code
• Validate submitted entries in less than 6 lines of code
• Customizable code length
• Customizable character sets
• TTF font support
• Use custom GD fonts when TTF is not available
• Easily add background images
• Multi colored, distorted, and transparent text options
• Customizable Flash button to stream MP3 audio of CAPTCHA code
• Use a word list for generating codes

Download: Securimage 2.0.1 BETA (zip)
Demo: demo

Adium is a free instant messaging application for Mac OS X that can connect to AIM, MSN, Jabber, Yahoo, and more. Adium is written using Mac OS X’s Cocoa API, released under the GNU GPL and developed by the Adium team.

Based on the libpurple protocol library, Adium can connect you to any number of messaging accounts on any combination of supported messaging services and then chat with other people using those services.

Notable Features

• A delightful UI
  • Tabbed chat windows
• Mac OS X integration
  • Address Book integration
  • WebKit Message View: Theme your chat windows
• Combined Contacts: Merge your contacts so that each one represents a person, not an account
• A sophisticated events system (including Growl notifications)
• OTR Encryption
• File Transfer
• Xtras and many, many other customization options
• A beautiful icon, the “Adiumy” duck
• Translations: Adium speaks 27 different languages

Requirements: Mac OS X 10.4 or newer
Download: Adium 1.3.10
License: GNU GPL

Digsby is an easy to use application, form which you can manage all your existing IM, email, and social network accounts. Digsby supports Instant Messaging, Email Notifications, Social Networking and many more features. All the features you can view here.

Instant Messaging – digsby is a multiprotocol IM client that lets you chat with all your friends on AIM, MSN, Yahoo, ICQ, Google Talk, and Jabber with one simple to manage buddy list.

Email Notifications – digsby is an email notification tool that alerts you of new email and lets you perform actions such as ‘Delete’ or ‘Report Spam’ with just one click.

Social Networking – digsby is a social networking tool that alerts you of events like new messages and gives you a live Newsfeed of what your friends are up to.

Download available for mac, windows, linux.

Download: http://www.digsby.com/download.php

AMANDA, the Advanced Maryland Automatic Network Disk Archiver, is a backup system that allows the administrator of a LAN to set up a single master backup server to back up multiple hosts to a single large capacity tape or disk drive. Amanda uses native tools (such as GNUtar, dump) for backup and can back up a large number of workstations running multiple versions of Unix/Mac OS X/Linux/Windows.

Amanda uses a native Windows client to back up Microsoft Windows desktops and servers.

Features of Amanda:

* Written in C and Perl.

* Built on top of standard backup software: Unix dump/restore, GNU
Tar and other archival tools. It is extensible to support new
archival applications.

* Open file and tape formats. If necessary, you can use standard
tools like mt and GNU Tar to recover data.

* Backs up 32 and 64 bit Windows machines.

* Will back up multiple machines in parallel to a holding disk. Once
a dump is complete, Amanda will copy finished dumps one by one to
virtual tape on a disk or tape as fast as it can.

* Maintains a catalog of files being backed up and their location on
the media.

* For a restore, tells you what tapes you need, and finds the proper
backup image on the tape for you.

* Supports tape changers via a generic interface.  Easily
customizable to any type of tape library, carousel, robot,
stacker, or virtual tape that can be controlled via the unix
command line.

* Supports secure communication between server and client using
OpenSSH, allowing secure backup of machines in a DMZ or out in the
Internet.

* Can encrypt backup archives on Amanda client or on Amanda server
using GPG or any encryption program.

* Can compress backup archives before sending or after sending over
the network, with compress, gzip or a custom program.

* Many more

Download: http://www.amanda.org/download.php
License: University of Maryland (BSD style) license and GPL