Sine Wave Cafe took over the 4810 Santa Monica Ave coffee bar in the former Espresso Lab Cafe space under surfer-owners who built the cafe around a music-and-ocean theme — the sine wave as a metaphor for both pure tone and ocean rhythm. An in-house breakfast calzone program — bacon and savory veggie builds — runs alongside egg salad toast with house tomato jam, avocado toast, and croissant sandwiches in a coffee-shop format that overlaps the OB morning trade with nearby Little House Coffee. Espresso, matcha, and iced-coffee drinks ship with no upcharge for oat, almond, or other alternative milks, plus a discount for guests who bring reusable mugs as part of the compostable-cup-and-lid sustainability program. Local artist exhibitions and musician sets turn the dining-room walls and counter into a rotating gallery and acoustic stage, building a community-arts-cafe identity distinct from the deli-counter lunch format that anchors the OB midday at Poma's Italian Deli on Bacon Street. The morning-through-early-afternoon seven-day kitchen handles the highest-volume morning-and-brunch window for the small Santa Monica Ave room, with calzone catering trays and group-order coffee drops booking up event-day mornings through the Clover online ordering system.