Yahoo Messenger Protocol

Recently I had to update a client messenger SDK so that it can log in to Yahoo Messenger service because Yahoo changed their messenger protocol and they no longer support older versions of the protocol. The latest YM9 uses YMSG v16, whereas the messenger SDK that I had to update used v12. So, I had to analyze and change quite a lot of things like login mechanism, buddy list parsing, presence, contact authorization, messaging etc. The login mechanism is explained here. I also found help by looking into Pidgin/Libpurple source code.

Multi-User Chat XEP-0045

I have been working on implementing XEP-0045 lately. This is an extension for XMPP protocol that enables multi-user chat or room chat. You can find the specification here:
http://xmpp.org/extensions/xep-0045.html

Browser Helper Objects

Recently I worked on a small project where I had to make a Browser Helper Object(BHO) for Internet Explorer. BHOs are also known as add-ons. A BHO is like a plugin that is loaded automatically whenever IE is loaded or a new tab (IE7) is opened. It's amazing how useful a BHO can be. I found this tutorial useful to get started:
Building Browser Helper Objects with Visual Studio 2005