Cursor locked in status line - no way out

[Thorsten]

hi List, 
I dont know how I did it, but I managed two times now to lock my cursor
in the status line with no way out but shutting down (the emacsclient). 
The cursor sits then close to the line-number symbol, and when I press
C-p or C-n the line number change (e.g. from L10 to L9 and L11), but
there is no visible cursor on the screen anymore. 
Hitting all the usual keys (C-g, ESC) did not help me out. 
Anybody knows what feature of Emacs I discovered here by some finger slipping
on the keyboard?

my system: 
"GNU Emacs 24.0.93.1 (x86_64-unknown-linux-gnu, GTK+ Version 2.24.10)
 of 2012-02-07 on arch
Org-mode version 7.8.03
Ma Gnus v0.2"

-- 
cheers,
Thorsten