Folks,
Just to add my two cents in here. I don't use the two char prefix on table field names. My primary reason is trelated to PK and FK situations. I believe that if there arte two fields that share the same domain they should have the same name. A PK and FK by definition share the same domain, therefore they should have the same name. Using table prefixes precludes the two from having the same name.
Taking that position a step further, if some of the fields don't follow the prefix convention then that convention is not being used conssitently. A convention that is not used consistently is not very valuable.