(written from a Production point of view)
Lou Wagner (born 14 August 1948; age 70) is an actor who played two different Ferengi in two Star Trek spin-off series. He first portrayed DaiMon Solok in the Star Trek: The Next Generation sixth season episode "Chain of Command, Part I" in 1992 and later Krax in the Star Trek: Deep Space Nine first season episode "The Nagus". His costume from his latter appearance was sold off on the It's A Wrap! sale and auction on eBay and was also worn by Frank Corsentino and the jumpsuit was reused by Rob Steiner. 
Wagner, who was born in San Jose, California, is well known for his roles in two Planet of the Apes films (1968 and 1972, with James Daly, Paul Lambert, Billy Curtis, Jane Ross, Felix Silla, James Gregory, Jeff Corey, Ricardo Montalban, and Paul Comi). He played the role of Harlan Arliss in the television series CHiPs (1978-1983, starring Robert Pine and Michael Dorn). Beside his on-screen roles he also performed the role of the professor in the McDonald's television commercials for over fifteen years.
Among his acting credits are films such as Airport (1970, with Whit Bissell, William Boyett, and Celia Lovsky), Columbo: Mind Over Mayhem (1974, with Robert Walker, Arthur Batanides, and Charles Macaulay), The Baltimore Bullet (1980, with Arell Blanton, Shay Duffin, and Ed Bakey), In This Corner (1994), Galgameth (1996, with Time Winters, Ken Thorley, and Stephen Macht), James Dean (2001, with Joanne Linville, Andrew Prine, Mark Moses, and Mark Kiely), Chopping Block (2005), and the short comedy Lowballers (2006).
Wagner has guest-starred in television series such as Lost in Space (1967, with Bill Mumy), Dragnet (1968-1969), Quincy M.E. (1979, with Robert Ito), The Golden Girls (1992, with Mario Roccuzzo and Rudolph Willrich), L.A. Law (1993, with Corbin Bernsen, Larry Drake, Lawrence Dobkin, Leland Orser, and William Utay), Providence (1999, with Leslie Silva and Molly Hagan), and My Name is Earl (2006).
He is also a member of Fred Willard's Moho sketch group and acted in several stage plays. He studied acting under Lee Strasberg, Madeleine Sherwood, and James Frawley.
More recently, Wagner had recurring roles in episodes of the comedy series Funny Or Die Presents... (2010, with Kevin Grevioux) and the comedy series Raising Hope (2010-2013, with D.C. Douglas and Ed Begley, Jr.).