The treble crochet stitch (tr) is one of the tallest stitches I have come across in patterns. There are taller ones, just add more yarn overs before pulling through your stitch, but this is the most common that I've seen. This stitch leaves you with an even more hole-y look than the double crochet stitch. It works up very quickly.
The video for how to make this stitch is listed on the directory of stitches.
Treble crochet stitches
Double crochet stitches (left) next to treble crochet stitches,
From left to right: Single crochet, double single crochet, double crochet, treble crochet.