So, normally when I run eclipse it is shown in both alt+tab and unity launcher. Now I have a running eclipse, I minimised it and I can't switch to eclipse any more.
Is there other way to switch back to an application without using unity launcher or alt+tab?
Pressing Super+W spreads all the windows out, so you might find it there.
If you don't, you can launch gnome-panel from the terminal (if it's installed) to get a GNOME 2 style taskbar, also seen in the screenshot above.