Using Web 2.0 in Corporate Environments

In my organization, learners are limited to search capabilities and tools outside of the organization's approved sites due to a firewall.  With more and more learners utilizing Web 2.0 technology, how is one expected to work within the confines of corporate limitations, such as firewalls?

There are many benefits to Web 2.0 for learners:

• Collaboration is encouraged
• Comfort level of users is high
• There is low cost to use the tools (Google Web 2.0 tools are free to use)

The question is how do you incorporate Web 2.0 into Corporate America in order for learners within these organizations to benefit from such tools?

I discovered this interesting article below that discusses protecting intellectual properties, etc., which leads me to another question - how do you get your organization to buy into utilizing Web 2.0?

http://content.arma.org/IMM/JanFeb09/Walk_In_The_Cloud/web_2.0_issues_risks.aspx