Vim

]] Jump forward to begin of next toplevel
[[ Jump backwards to begin of current toplevel (if already there, previous toplevel)
]m Jump forward to begin of next method/scope
[m Jump backwords to begin of previous method/scope

][ Jump forward to end of current toplevel
[] Jump backward to end of previous of toplevel
]M Jump forward to end of current method/scope
[M Jump backward to end of previous method/scope

I use plugin tcomment for commenting lines. Keybindings are:

gc{motion}          :: Toggle comments 
gc<Count>c{motion}  :: Toggle comment with count argument                   
gcc                 :: Toggle comment for the current line