I do this, although I use column view.
I removed all of the items in the sidebar by either dragging them out or using the preferences. Then, double clicking on the seperator compresses the sidebar. There is a problem, though. Occasionally, I'll get a CD, DVD or dmg that will open its own window that will have the sidebar open part way. Peculiar looking, but not too much of a nuisance. I would actually prefer that they didn't open a window at all.