The regular expression is probably the best solution, but I would like to add this one, in case it is more appropriate for what you are doing, and also because it is easier to use for people that do not know regexp.

If all lines have the same length (same amount of text), you could use the "Column Mode" from the "Extra Selection" plugin. You position the cursor at the end of the first line, enable the "Column Mode" from the "Tools > Extra Selection" menu, then you press Shift and arrow down which make the cursor goes multiple lines:
(I use the character "|" to represent the text cursor)
aaa|
bbb
ccc
ddd

Shirt + Arrow down 3 times:
aaa|
bbb|
ccc|
ddd|

Then you type your text "ZZ" and it appear at the end of every selected lines:
aaaZZ|
bbbZZ|
cccZZ|
dddZZ|

Don't forget to disable the "Column Mode" when you are done. It can be quite annoying when you don't need it :)

Gael

On 29/06/13 17:03, Philippe Couas wrote:

-- 
Gael Lafond, Programmer
Australian Institute of Marine Science
PMB 3, Townsville MC, QLD 4810
Ph 4753 4207 - g.lafond@aims.gov.au