An enterprise search play by Microsoft, a $1.2 billion purchase of Norway-based Fast Search & Transfer, may be on the minds of Google.

The vibration felt at Google may be nothing more than a plastic teacup dropping onto the carpet a mile away, but it appears they aren’t taking a chance at letting Microsoft gain momentum in enterprise search.

A little of The Fear stopping by the Googleplex for M&Ms, perhaps? The Google Enterprise blog exhorted business-types to “make a fast switch” to Google’s products.

Aside from advertising revenue, Google does some business with search appliance hardware. Their non-ad business represented about a fraction of a hundredth of the company’s revenue, based on its last SEC 10-Q statement.

Even so, Google wants people to continue to associate it with search, above and beyond the web-based version where they made their fortunes:

Last week’s developments in the enterprise search market are sure to bring confusion and uncertainty to many customers. Customers of existing enterprise search solutions will start wondering about the future of the investment they made in the past. Is their product still going to be developed and improved? What about support for a diverse enterprise IT landscape? How long before they’re asked to do a painful – and costly- migration?

Long-time Microsoft observers may recognize Google’s stance here as a familiar one: the old fear, uncertainty, and doubt approach. One can hardly think of FUD without recalling Microsoft’s campaigns against Linux in the last decade.

Yet undisputed search leader Google took this shot nonetheless. An interesting tactic from a company not usually associated with worrying about the competition.

Microsoft’s Fast purchase brought more than just the enterprise search technology to Redmond. It also pulled along a challenge for Microsoft to hammer out a unified enterprise search strategy. If Microsoft can quickly integrate Fast into a product like its SharePoint server, they will have a big selling point to emphasize to prospective clients.

That selling point, we are positive, will include suggestions that a client won’t need a separate search device, like, say, a Google search appliance, to accomplish their internal needs.