of Delrina's Opus 'N Bill screen saver in which Opus the Penguin shoots down the toasters. Delrina later changed the wings of the toasters to propellers in order to avoid infringing the trademark. The second case was brought in 1994 by the 1960s rock group Jefferson Airplane who claimed that the toasters were a copy of the winged toasters featured on the cover of their 1973 album Thirty Seconds Over Winterland. The case was dismissed, because the cover art had not been registered as a trademark by the group prior to Berkeley Systems' release of the screen saver. Boyd and Blades went on to found the liberal political group MoveOn.org in 1998. Blades also later co-founded MomsRising.org with Kristin Rowe-Finkbeiner in 2006. References External links https://web.archive.org/web/19970102213049/http://berksys.com/# ,Archived version of official website (berksys.com)] Software companies based in the San Francisco Bay Area Macintosh software companies Defunct video game companies of the United States Video game development companies Companies based in Berkeley, California Software companies established in 1987 Video game companies established in 1987 Video game companies disestablished in 2000 1987 establishments in California 2000 disestablishments in California Defunct companies based in the San Francisco Bay Area Sierra Entertainment