For the Emacs users, pc-selection-mode is more intuative than the normal selection mode
For Vim users: Ctrl-V is rectangle selection and is very useful
In Python you can apply a function to a whole List with the map() function:
This will output [1,2,3].Code:print map(lambda x: x+1; [0,1,2])
ngrep is really useful for watching traffic on your computer.