Fab 40 templates were free templates released by Microsoft for sharepoint 2007 and wss 3.0 to address some of the common scenarios encountered by SharePoint administrators, developers and event business/Marketing managers to demonstrate and show case some of the capabilities of MOSS to end users.
Discussion about that how good these templates are and in which scenario these are more helpful versus things which needs to be improved in these templates is a separate topic but I have noticed many SharePoint people using these templates either for small clients , for demonstration purpose and even for training purposes etc. ..
I have uploaded some of these Fab 40 templates for SP 2010, so now you can have Fab 40 for SP 2010, at least some of these are available for now…rest coming soon J .
Follow the instructions in readme file to install these, I strongly recommend that you install it in your test environment before testing it in real/production.