How to resque a hanging linux

key 
 function 
 
 
 r 
 Remove
X's control over the keyboard 
 
 
 e 
 End
all processes except init (SIGTERM) 
 
 
 i 
 Kill
all processes except init (SIGKILL) 
 
 
 s 
 Write
diskcache to disk 
 
 
 u 
 Remount
all mounted filesystems read-only 
 
 
 b 
 Reboot!