Since WordPress 2.5 there aren’t any links to the post drafts in the edit post section, so I’ve made a quick plugin that simply displays a box with the last 10 recent drafts in edit post page, as an unordered list, sorted by the last edit time.
The list is populated with the drafts titles, linked to the edit post page of each. The box is shown only to users with Editor role or higher.
In WordPress 2.7 or higher the box is displayed in the sidebar of edit post page, under the categories.