Thanks all. As an FYI the pictures are off the web just to clarify what I was talking about for plugs.
The other day I ran into a plug I could not get. It was a weird set up in a 100+ year old duplex and I was afraid of breaking the pipes when I put my weight into it. Normally I would do as Rick said, use my pipe wrench with an extra pipe on the end for leverage. But alas, I did not have an extension pipe with me. So I got to thinking maybe there are some other tactics I'm not thinking off. Heating them don't seem to do much; or maybe I'm not getting them hot enough.
Guess I better keep that big pipe in the van from now on.