Psi is the premiere Instant Messaging application designed for Microsoft Windows, Apple Mac OS X and GNU/Linux. Built upon an open protocol named Jabber, Psi is a fast and lightweight messaging client that utilises the best in open source technologies.
The goal of the Psi project is to create a powerful, yet easy-to-use Jabber/XMPP client that tries to strictly adhere to the XMPP drafts and Jabber JEPs. This means that in most cases, Psi will not implement a feature unless there is an accepted standard for it in the Jabber community. Doing so ensures that Psi will be compatible, stable, and predictable, both from an end-user and developer standpoint.
This does not mean that Psi will never have “cool new features”. The dev team and community are power-users who look to Psi to keep up with the times. We always want to hear what the users of Psi would like, and if a feature that the dev team wishes to implement does not have an accepted standard, or would diverge from an existing one, we can work together to see the standards changed to accomodate everyone.
Perhaps you have been considering Jabber, but don’t want to abandon your friends? Jabber technologies are highly extensible, so Psi is able to interoperate with other, proprietory messaging systems such as AOL’s ICQ and Microsoft’s Messenger. You can keep in contact with your friends, regardless of whether they use AIM, ICQ, MSNM or YahooM. It’s even possible to use Internet Relay Chat!
Unlike other IM clients, Psi is small, fast and responsive. It uses a graphical toolkit called Qt, which takes on the appearance of whichever operating system you run it on. For this reason, Psi doesn’t use ‘skins’. We’d rather it blend with your desktop like any other application.
Psi has full support for Unicode. Unicode allows Psi to send and receive messages in other languages, even ones that aren’t based upon the English letterset. In fact, you are able to use Psi in your choice of eight different languages, with more on the way!
Cross-platform compatibility is important to the Psi development team; we believe that you should be able to use whichever operating system you wish. In keeping with this belief, we have a version for each of the three major OS’s. The images on this page show Psi running on Microsoft Windows XP, Apple MacOS X and GNU/Linux/KDE3.
Download Psi 0.10 (Windows 98/2000/XP Installer (3 MB)
Mac OS Disk Image (5.97 MB))