Redirecting PR and Links

What should do? 301? Cloak? Other?

[mrwhy2k]

I am setting up a new site about widgets, we'll call this site A.
And I bought a site (Site B) that is number #3 in Google for "Widgets". Site B has a decent PR and some good backlinks, Yahoo, DMOZ, ect.

I would like to keep Site B in the same ranking it currently has but at the same I would like to redirect all that traffic to Site A, my new site.

How do I maintain the current rankings for Site B but redirect all traffic to Site A. I don't want to keep Site B around, I want to shut it down and redirect PR, Links and traffic to Site A. Any good way to do this?