Gillian Anderson is noticeably shorter than David Duchovny, with a height difference of approximately 10 inches between them. This created a challenge during their time working on The X-Files, as filming their conversations in full shots would have had Anderson looking up at Duchovny's chest (which, while not the worst fate, wouldn't have made for great TV). The clever solution was the Scully Box, a customized version of the classic apple box. Anderson stood on this specially designed box to be elevated just enough for their interactions to look normal on screen. Take a look at the results:
Before the Scully Box, the standard solution for such challenges was the apple box
Some reports suggest Gillian Anderson affectionately called it the "Gilly Board," which is pretty charming. In a conversation with US Magazine, which was shared on Anderson's "official" website, the Scully Box (or Gilly Board) is mentioned without being named directly. It's interesting to note that Anderson appears to contradict herself during the discussion (emphasis added):
US: You walk very tall. Do you ever forget that you're only 5 feet two? GILLIAN: It depends on how I feel about myself in a given moment. Sometimes I forget I'm short. Sometimes I totally feel how short I am. US: Like when you have to stand on a box to do a scene with David Duchovny? GILLIAN: I don't have to stand on a box. Sometimes when we're in a situation walking side by side, like up to a door to pull out our badges and say we're from the FBI, I have to step up onto something so that we're on the same level. I mean, I don't walk on boxes or have boxes attached to my feet. It's funny: Sometimes I forget I'm on the box. Like, I'll have this very serious moment in a very serious scene and I'll turn to the camera and fall right off the box.
(Courtesy of The Beautiful Chaotic.)