Mountain View company Barracuda Networks is "pulling a Yahoo," a tipster tells us. Management told employees on Tuesday there will be a mandatory holiday break December 24 through December 28. "Yes, the only notice was a little more than two weeks before the forced PTO," our source notes. Despite what our tipster thinks, Yahoo's far from the only Valley company to pull this kind of stunt; Sun, Adobe, and others have forced employees to take vacations over the years. The Scrooge-like gesture does have the salutary effect of reducing the employer's vacation liability. If you work at one of these companies, just ask yourself: Which is worth more, your stock options or your vacation time? Here's the internal memo Barracuda sent to spread the holiday cheer.