The residents of Silicon Valley are more confused than usual after a billboard campaign by the National Multiple Sclerosis Society of America.

One of the ads uses the slogan:

"MS: It's not a software company"

Exploiting the fame of a certain company to draw attention to an altogether worthier cause.

Requests to comment on the campaign have been met by a surly silence by Microsoft which doesn't relish the association of ideas, but is painfully aware that it can't afford to appear insensitive over such an issue.

Seasoned IT professionals will have no trouble telling the two MS's apart:

- One is a debilitating and surprisingly widespread affliction that renders the sufferer barely able to perform the simplest task.

- The other is a disease.