Solidworks 2007 has a new push/pull capability that allows you the ability to tug on existing surfaces without creating construction curves. This will greatly simplify the ability to add a pimple on a surface if that's what you want.

More extensive changes can be made to a surface by broadening the scope of the deformation shadow. What's really cool is how solidworks handles the edge conditions once a surface has been tweaked. It snap the deformed edge back to the original edge so that your 3D manifold is still valid.

This is really cool, if you haven't seen it, you need to attend a 2007 rollout and watch this this new functionality.