Move special folders to new drive? (My Docs/Program Files)

[DJ in CA]

Can the default drive for newly installed applications
(Program Files) be changed from "C", to another local
hard drive? If so... how?

I also need to move "My Documents" to an alternate
drive. - I have no files from other users, or networks to
consider.

If anyone knows of a safe way to successfully move either
of these folders, a brief explaination of the proceedure
would be greatly appreciated!

Thanks!