Ubuntu 9.10, systray(system tray) icons are missing

Question

I was moving some panels on the Desktop and I accidentally clicked "Remove from Panel" and now my Sound, Wireless Networks Config, Battery Indicator, Dropbox, icons are gone.

I did some search in the menus and stuff trying to find a way to put them back again but unfortunately I couldn't find them. It must be a complete panel with icons, cause I pressed only 1 click "Remove from panel", and those 4-5 icons disappeared all at once..

Answer 1

Right click on the top panel, select Add to panel..., then re-add the "notification area" applet.