We've now been to the relatively-new Beckett's pub in downtown Berkeley (2271 Shattuck, between Bancroft & Kittredge) three times lately just for the burger! It's really a delicious one - juicy and big but not enormous. Good steak fries served with it. And pretty reasonable ($6.95 or so).
Tried the fish & chips, too - they just weren't good enough for me to spend $11.95 on, though the fish was very good quality and you get lots of it. Spinach salad w/hard-boiled egg, onions, and bacon was tasty, too, though I think crumbling the egg and bacon rather than leaving them in segments would be better.
Very nice, cozy, faux Irish atmosphere. Unfortunately they only serve food until 10pm, except on Sat. & Sun. until 11pm.
Samuel Beckett is rolling over in his grave.