Web 2.0 value in the Enterprise?

The use of Web 2.0 tools in the enterprise is becoming a very common discussion topic in almost every collaboration discussion I have these days. Unfortunately, I have not seen a lot of success stories for use behind the firewall but a lot of smart folks are thinking about it, really searching to show corporate value. There is generally the obvious request for "Facebook-type" functionality but it doesn't end there. I recently delivered a POC for a customer where we delivered some social networking capability using the OOTB features of MOSS as well as customization. This is a pretty exciting area and bound to explode over the next year.

If you have any good scenarios that demonstrate value to corporations I'd love to hear about them.

For those interested, the following articles I found real interesting:

Go Ahead, Use Facebook

Younger Workers Demanding Web 2.0 Tech On The Job