ALF made an appearance NBC 75th Anniversary Special, which aired on May 5, 2002. In one bit, Michael Gross of Family Ties complains to the host Kelsey Grammer about the person sitting next to him. It appears that he is talking about ALF, but then he explains that he and ALF came together and that he's actually complaining about David Hasslehoff, sitting on the other side, for continuously talking to Kitt with his watch.
The producer of the special, Tina Fey, reportedly complained that ALF's people were the most difficult to deal with in putting the program together. This is likely due to the technical requirements of hiding the puppeteer and mechanisms that are needed to make ALF appear as real as possible.