Teemu Keisteri (Finnish pronunciation: [ˈteːmu ˈkei̯steri]; born 22 August 1985) is a Finnish visual artist and DJ who is known for his stage persona Windows95man. As a visual artist, he gained recognition in Finland for his paintings and prints of the fictional character Ukkeli (lit. 'Old man'), whom he created in 2008. As a DJ, his artistic style and appearance draw inspiration from the mid-1990s, during which the Windows 95 operating system was released. He represented Finland in the Eurovision Song Contest 2024 with the song "No Rules! ", alongside singer Henri Piispanen.