One popular surfwear brand known for its logo t-shirts featuring a wave and palm trees is "Billabong." Billabong is an Australian clothing and accessories brand that specializes in surf and beach-inspired fashion. The brand's logo, which includes a wave and palm trees, is prominently featured on their t-shirts and represents their connection to the surfing culture and coastal lifestyle. Billabong offers a range of apparel and accessories for both men and women, including t-shirts, boardshorts, swimwear, and more, with designs that capture the essence of the surf and beach lifestyle.