More on VI...
H - position the cursor at the top of the screen (left most position)
M - position the cursor in the middle of the screen (left most position)
L - position the cursor in the bottom of the screen (left most position)
G - position the cursor at the bottom of the file (left most position); last line in file
gg - position the cursor at the top of the file (left most position); first line in file
:_n_ - position the cursor at line n of the file