I hear a lot of questions about which applications are included in which versions of Office. So, rather than rehash what is elsewhere, I'll point you to the Microsoft Office 2007 Suites page on Office Online.

Each suite has a different set of products included, targeted at different types of users... for instance, most students don't really use outlook (its all webmail, IM, facebook and beers for those people) - so they don't have to pay for it. Obviously, Australian students work so much harder they need all the features of Office Ultimate for cheap cheap prices (yes, it was legit). But anyway, I digress...

If you want to really get the full SharePoint to Office integration you need either Office Professional Plus, Office Enterprise or Office Ultimate.

And then SharePoint...

SharePoint is pretty simple, there are two main flavours - Standard and Enterprise. If you only want some features of Enterprise, you can just get the bits you want.

There are heaps of features in SharePoint, so I'll just point you to a very informative excel ECMA OpenXML spreadsheet here: MOSS 2007 Feature Comparison. The main point of confusion is with the more specific flavours:

if you don't want MOSS, but you do want Enterprise Search or Forms Server functionality, you can get these as standalone servers that build on top of WSS (just like the rest of MOSS).

What can I get for free?

As for WSS (Windows SharePoint Services), it is part of Windows Server 2003. I like to think of WSS as a framework for rapidly developing collaborative web apps. MOSS uses WSS as its foundation and anybody can use it to build their own applications on top of it as well.

If you are hosting a .NET web app, chances are you have everything you need to leverage some WSS components into your app. In a way you can look at WSS like the .NET framework itself!

This post is cross posted on Alistair's WSS 3.0 powered blog and his MSDN blog.