Twitter have released an open source HTML and CSS starter kit called Bootstrap. It provides defaults for front endy bits like typography, forms and buttons.
Better still, there's a Pinax theme based on it, making bootstrap
styling your forms as easy as
I can see this being a really handy starting point to get playground apps and prototypes up and looking reasonable without needing a frontender or designer. Well, until every other app looks like it and we get totally sick of it, obviously.