If I'm right, panel applet is no longer supported in Unity. How can I bring sticky notes back? Is there any application or AppIndicator that has the same functionality (like show all notes when logged in)?
Not tomboy please :), I don't like its interface.
Indicator-stickynotes is maybe the applet your looking for !
Written in Python, and using GTK 3 library. Current version is 0.3, but works well. You'll have to add this ppa to enjoy this application :
See here to run indicator-stickynotes on startup.
See “Simple” gnome applets in Unity - stickynotes
And here How do I use the GNOME Panel in Unity? Until someone makes an indicator for it those look like your work arounds.
Try Xpad : http://www.omgubuntu.co.uk/2010/08/xpad-simple-sticky-notes-for-your-desktop/
You can click on this link to install : Xpad
I haven't tried it personally but this indicator applet tries to copy the functionality of the old notes applet.