6. Jef Maynard, Patrick Brantseg and Beez McKeever were well known for their creativity when creating props for MST3K. Sometimes, however, Best Brains took the easy way out and just used some of their own merchandise as either a prop or a set decoration. Here's a table of what I've caught.
In Wild Rebels (207) and again in The Hellcats (209) Joel has one of his own coffee mugs sitting on the SOL desk. We briefly see in Time of the Apes (306) that there is an original MOVIE SIGN bumper stickler on the bottom of Joel's clipboard.
The same folder is laying on the desk in Earth vs. the Spider (313).
In Gamera vs. Guiron (312) while not the actual lunchbox sold by Best Brains that is a copy of the fan photo that used to come in the Life Survival Kit. A year later there would be a similar lunchbox sold to fans. The picture on the side of the facial tissue box seen during Space Travelers (401) is the fan photo of the Mad Scientists that came in the Life Survival Kit. Mike Nelson as Winkie shows up in the hexfield viewscreen in Manhunt in Space (413). He is wearing a slightly modified version of the original planet logo power t-shirt. In 12 to the Moon (524) while Frank roast Dr. Forrester there is a BBI poster of the good doctor on the front of the podium. Dr. F gets some revenge on TV's Frank on wash day during The Creeping Terror (606). That's a cut out from the Frank poster being put through the wringer. Not sure why the image is reversed. Once again Dr. Forrester takes out his frustration on Frank while clad in his Property of Deep 13 t-shirt. This killer dodge ball game was at the end of The Skydivers (609). Crow finally gets a chance to direct his movie Earth vs. Soup and dons a Deep 13 hat during The Incredible Melting Man (704). During the intro of MST3K: The Movie Dr. F is wearing a BBI wrist watch. Strangely he is also still wearing his own watch on the same wrist. Although not sold per se by BBI a copy of the Satellite News did appear in the movie. It is issue 6.2 Holiday 1994. Which came first: the chicken or the egg? Or in this case: the You Know You Want Me, Baby t-shirt or the host segment in Overdrawn at the Memory Bank (822)? Is this a little too blatant to still be called product placement?