Writing PowerPoint Plugin

[Dimple]

Hii Everyone,

I am a software developer and would like to know if there is some link or
information available to show me as to how to write Plugin for Powerpoint.
Basically i am interested in writing plugin for powerpoint where while
viewing the slide show i can have my own custom toolbar which helps me zoom,
view other images etc.

I dont have much luck w.r.t finding some good information. I would also
like to know if it is possible to write the plugin in C# as i am more
familiar with it.

Any help in this matter will be appreciated.

Thanks in advance