The way you get dropped sts for just a few rows, is to make a YO between 2 sts somewhere, then after 6 or 8 row, drop that st and let it fall to the YO. You can do one every 10-12 sts or so, then when you've dropped all of them on a row, make another yo between the ones you just dropped. I've seen some patterns that have that effect, but don't know the names of them to link for you.
I found a scarf with this technique - http://www.breihemel.nl/files/drop_stitch_scarf.pdf
and there's the Drop-stitch Lace Tank from Fitted Knits, another Ladder Tank http://www.bluealvarez.com/bluealva/...addertank.html
And a few more in various magazines and books.