I've only been here twice (my sister introduced me to it), but Diddy Riese is such a fun place to visit for the best ice cream sandwiches ever.
Plus, they sell a dozen day old cookies for only $2. I wish I had bought more cookies to bring home as souvenirs for family (but maybe I would have eaten them first, so maybe it's a good thing I didn't!)
It's in LA next to UCLA. And if you want to park for free, just park in the Target parking lot about 2-3 blocks away and buy something there, they validate for 2 hours.