favorite pattern for what?...LMAO
for bags, I like the booga bag and buttonhole bag patterns becasue there's SOOOO much you can do with them, from intarsia to simple stripes, plus they're really easy to alter to make different sizes.
for socks, I don't have a favorite, because I LOVE LOVE LOVE SOOOO MANY of them. The same is true for adult sweaters.
for babies, for girls I LOVE to knit the Summer Swing Top from freepatterns.com. For boys, I love to do a simple top down raglan cardigan, for the same reasons I love the bag patterns. it's SOOO very simple to customize.