Some 4 thread and some 5 thread sergers do a blanket stitch without all the gimmicks and tricks that we used to have to do to try to get a decent blanket stitch. One thing for sure the sergers that do that stitch really do it well! You can put an assortment of different decorative thread(s) in the needle and WOW what a beautiful stitch. Of course check your manual for guidelines before attempting this stitch. I love to use that stitch to make scrungie hair ties for pony tails.
A quick and ez gift idea. Take two 2" x 45" strips of fabric ( less length if desired). Fold under and press the short ends. Then with wrong sides together - go for it and serge a blanket stitch down both long sides. Finally take a small strip of 1/2" elastic and run it through. Tie the ends of the elastic in a knot and WOWEE - a gift for a any occasion! I can think of a thousand different uses for that wonderful blanket stitch - just ask me??????????????