Developing a Hybrid Intranet
One of the wonderful things about the internet is that a global community of developers has gathered to create and innovate, and to share. Many developers work on their own or in collaborative groups to create code, tools, applications and tutorial web sites where other developers can learn, beg, borrow, buy, and steal from them. As a legitimate corporate intranet builder, you are an elite client for many of these developers and will probably get very positive responses when you begin shopping for functional components.
The best place to start looking for the additional functionality pieces of your intranet, if this is the approach you're taking, is by searching the Web for specific components or going directly to a developer community site like http://www.evolt.org, http://www.sitepoint.com or http://www.siteexperts.com. Most of these sites have discussion groups where you can post e-mail queries and requests for proposal (RFP).
Another option is to visit community code portals like http://www.aspin.com, http://www.planet-source-code.com and http://www.programmersresource.com and literally browse and compare products like you were shopping in a retail establishment.
While the cost of this type of solution is attractive, the drawbacks are similar to those articulated in the section on developing an intranet internally.