In Problem Sleuth
The whores apparently didn't understand what treasure they had possessed, since Nervous Broad found it simply laying on the floor in the sleazy brothel in the sky when she arrived. Nervous Broad donned the eyewear and was granted the ability to see all events in the future of the universe.
Towards the end of the adventure, Godhead Pickle Inspector obtained a pair of sunglasses that bear more than a passing resemblance to the Ben Stiller Bust's. In fact, considering the way GPI used them to view all of creation, it is possible that he somehow came into contact with Nervous Broad and took her glasses, and then increased their size so he could use them.
Dave Strider is given a strikingly similar pair of sunglasses by his friend John Egbert, accompanied by a signed photograph of Ben Stiller, because Dave is just that cool. It appears to be the photo that was used as a reference in the carving of the Ben Stiller bust. In fact, the universe reflects off of them when Dave is named correctly, much like when GPI wore them.
Bro has another pair of sunglasses which are triangular. Dave is wearing a similar pair on his birthday, the same day he received John's gift. Dirk Strider is also shown to wear these and has even turned them into a sentient entity.