Good article in eWeek about the disruptive nature of collaboration tools:

The most recent problems came to light when a network failure cut off e-mail and Web access throughout the company's far-flung operations.

Instead of simply calling it a day, creative employees quickly implemented workarounds. One group installed a quick and dirty Wiki to enable team communications.

Another took advantage of America Online Inc.'s Instant Messenger application to route files and messages between geographically remote employees. Others used Web e-mail and wireless networking to keep the company's business flowing.

The CIO's response was predictable: He moved quickly to lock down corporate desktops and laptops to prohibit users from installing unapproved software or accessing unsupported Web services.

It's not the first time I've seen such a dramatic, knee-jerk response to user-supplied productivity tools. In fact, the rise (and attempted squashing) of new collaboration tools, social networks and wireless connectivity today has eerie parallels to early PC adoption. And despite the best intentions of corporate IT, the results will be the same.