Aurora is a new commercial LaTeX system for MS Office
Update: a newer system to write equations in PowerPoint is called TeX4PPT.
I am just preparing the PowerPoint support for a string theory lecture on Wednesday. You can see the relevant files in various directories on the course web page
http://www.courses.fas.harvard.edu/~phys287a/
Although PowerPoint is pretty useful and looks good, writing equations in PowerPoint is not the most convenient thing in the world - and the blackboard remains the most available substitute. In principle, Microsoft offers a WYSIWYG environment called "Microsoft equation editor", but one needs to go through a lot of hassle if she wants to type a single equation. Most of us (physicists) are used to write equations in TeX.
This is the reason why many of us can appreciate a nice addition to the PowerPoint which is called "TeXpoint", see
http://raw.cs.berkeley.edu/texpoint/
TeXpoint offers two modes - limited LaTeX and full LaTeX. The limited LaTeX mode allows you to type a TeX-like mathematical expression with superscripts, subscripts, integral signs, Greek letters (written with the usual backslash commands), and so forth, and then press alt/x alt/x. Suddenly, all these objects are converted into a pretty reasonable form. I am using it all the time. Well, fractions are impossible - the output generated by this simple tool must be a linear sequence of characters.
On the other hand, the full LaTeX mode, initiated by alt/x alt/d, quickly opens a window where you can edit the body of a LaTeX source, and by two more clicks, you can generate a PNG image from that LaTeX source, which can be pasted to your PowerPoint file immediately. Although the result is, in principle, a perfect TeX image, I am not using this option too much because it does not handle the vertical position of the equation and the color of the background too well, and moreover, it is much slower than the limited TeX.
It's probably more reasonable to make a "snapshot" of an equation as seen in the Adobe Acrobat Reader. If you have the new reader 6.0, you should try to play with the "camera" icon. This tool is able to take a rectangle from a PDF file, convert it to an image file, and copy it to the clipboard. You just switch to PowerPoint and "paste" this image. That's it.
One more general comment. Microsoft is doing a great job, and Bill Gates is one the most deserved billionaires in the history of this planet. It was probably a very good decision for him and for most of us not to finish his studies at Harvard. As you see, this blog is not going to join the club of narrow-minded anti-corporate blogs that copy all this cheap stuff from each other!