Last week's round of investment in Facebook is enough to make any Dot Com veteran quake in their boots. It's not that Facebook isn't good - it's stunningly good. It's not that this particular dance involving Microsoft and a fresh young company hasn't been danced before, either - just take a look at High stakes, no prisoners for a good idea of some of the behind-the-scenes shenanigans that undoubtedly went on.

In short, Microsoft invested $240m, and two unnamed hedge funds plumped up another $500m, valuing Facebook at $15bn. It's a stunning number, something we haven't seen in a long time. Rightly, it scares the living daylights out of many people, myself included. It brings back memories of years past, when  things were valued on the basis of hype, on the basis of an ever-lifting market, on the basis of a new technology trouncing the status quo and ushering a new dawn of techno-wonderous utopia. But enough about the telegraph.

However, there's another way of looking at the investment, particularly from Microsoft's angle, that makes a little more sense. Remember Microsoft's recent moves into advertising? Chucking $6bn at aQuantive is a far bigger investment than a piddling $240m at Facebook. Any lay person might assume that Microsoft valued aQuantive more highly in terms of business use than Facebook; after all, it's punting  over 24 times the money on aQuantive than it is on Facebook. Of course, it's not that simple, but it's an interesting thought.

Techdirt has itself a very juicy idea of what Microsoft is up to - and it's all about aQuantive and Facebook's advertising plans. In short, the investment in Facebook is a place holder, something that makes a marketing statement about Microsoft's intentions in online advertising. I can't wait to see all of this play out.