A couple of bookmarks:

Smart Client Developer Center (Consume)
Web Services Development Center (Provide)

Why list these bookmarks on an Excel site? One of the best examples of a Smart Client is Office(source video), however I’m sure you already knew this<g>.

A few thoughts from an “Excel as a Smart Client rookie”:

Note: From the definition of a Smart Client: “Smart client applications come in many shapes and sizes with varying degrees of functionality.” When I refer to Excel as a Smart Client in the following text I define it as “a spreadsheet which connects to Internet or Intranet servers to consume services, enhancing an Excel solution beyond Excel’s default capabilities.”

I love the concept of an Excel Smart Client.
I would love to be able to take something as simple as a contact list in Excel and also have at my finger tips information about the weather, news, hotel room availability, top restaurants, etc. for each contact’s location(It would at least help with the small talk).

Or develop a construction spreadsheet that could use a webservice like TerraServer’s webservice to immediately show an aerial view of each property they had a worksheet for(this would be much nicer with Keyhole).

Or many other creative solutions, but:

I struggle with the reality of an Excel Smart Client.
Documentation for a web service is usually a headache, if it even exists.

Finding a reliable web service is a chore(at least free ones).

I need to install an unsupported Toolkit(“hack”) to consume web services in Excel.

Microsoft says the best way to develop an Office Smart Client is not to use Office at all, rather VSTO(Visual Studio Tools for Office).

The average Excel user will most likely not be able to use Excel as a Smart Client the way things are now. My advice today would be “go get a CS degree”.

There is Hope!
Check out what the people at StrikeIron are doing with On Demand Web Services for For Excel(Beta).

“StrikeIron OnDemand Web Services for Microsoft

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