Recently I wanted to return to using Stickies again. However, when I went to create a new note, it opened in the collapsed state. Selecting deminimize from the Window menu caused it to disappear! I could still type and save the note, but its graphical representation was nowhere to be found.
After much fretting and using every menu/window button combination I could think of, I decided to trash the preference file (com.apple.Stickies.plist in your user's Library/Preferences folder). I backed up the existing notes first (these functioned normally), since I was not sure where their data was stored. After trashing the preference file, everything worked fine.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20040607140805135