The latest commercial that I like is the one for the Maple Leaf roasts that you just shove in the oven; they show a stay-at-home-parent bending over the oven, wearing tight pants making their bum look big, so you assume it's a mom, then the parent turns around & it's the dad! That one cracked me up the first time I saw it, & I still like it.
I still like the Diet Pepsi commercials that ask, what would you like to have back. There's the 80's hair, the van, & some others that I can't think of. Those ones are pretty good too.
The commercial right now that I can't stand is the one for Virgin Mobile phones where the girl is opening her Christmas present & it is a hair dryer, she starts to hiss & then a stuffed moose on wheels comes into the room & delivers a phone, then the freaky dude beside her starts cheering. I hate that one mostly because I just don't get it.