Ok, you are in the pattern editor and want to do something funky.
Here is some hotkeys probably not so well-known to masses.
[ALT]+[W] - select 8 rows on all tracks
[ALT]+[Q] - gradual [sample/vol/pan/efx] selection of 8 rows in current track
[ALT]+[S] - select all tracks above cursor
[ALT]+[X] - select all tracks below cursor
Know something better in terms of hotkeys?
Drop your information here.