Microsoft's desperate struggle to acquire all or part of Yahoo! has gotten hung up not on disagreement over a fair price for the latter’s online advertising operations, sources say, but rather the value of Yahoo!’s iconic exclamation point.

"Ballmer just won’t budge on this, uh, point," says one source close to the negotiations. "He told me, 'Hell's bells, you can look up 'exclamation point' in any dictionary and see a picture of me next to the definition. Why should I pay a penny for theirs?’ "

Yahoo! isn’t asking for pocket change. When Microsoft earlier this month pulled the plug on its offer of $47.5 billion, or $33 per share, Yahoo! was reportedly demanding at least $1.50 per share more -- about $2 billion -- exclusively for the exclamation point. This despite the fact that Yahoo!’s founders only added the mark after discovering the unadorned word Yahoo had already been locked up by a barbecue sauce maker.

With news last week of a renewed overture by Microsoft, it’s possible that Ballmer may be softening on his not-a-penny-for-the-point position.

Experts insist he has no choice, given the ample precedent for corporations placing hefty price tags on their famous punctuation. And, as one noted to me, the exclamation point on Yahoo!’s home page may be the only one on the Internet that actually yodels when clicked.

"That alone tacks a couple hundred million on the price," he said.

Wall Street types familiar with the situation inevitably recount the 2005 war between SBC and AT&T over the valuation of the latter’s ampersand. At one point the negotiations nearly broke off after SBC claimed it had no intention of paying for the ampersand because it had no intention of retaining the AT&T moniker.

"Threats don’t get any emptier," a source told me. "That $16 billion deal was a $15 billion deal without the amp."

In its fiscal year 2007 filing with the Securities and Exchange Commission, EMC2 affixed a $50 million "estimated market value" on the company’s exponent, while noting that it would be significantly higher if more people knew what it meant or how to create one in Microsoft Word (type a normal 2, highlight it, press ctrl, shift and the plus sign simultaneously).

"Everybody knows the Yahoo! exclamation point," my source noted, "and the [bleeping] thing yodels. EMC’s silly little two doesn’t do squat."