Okay, backing up a tiny bit.  During the end credits of Ridley Scott's Alien prequel, there weren't any comic book-style Easter Eggs, nor was there a comedic compilation of outtakes.  But there was a shout-out to the website: Whatis101112.com.  Since this a viral promotion site, it does not, in fact, answer the question, but we assume something Prometheus-related will occur on October 11th of this year.  The site instead fits the Weyland Corporation template, and includes a floating copy of 19th Century German philosopher Nietzche's novel Thus Spake Zarathustra, with the quotation "What is great in man is that he is a bridge not an end" on its cover.

The site also contains a very short video of Weyland, presumably just before the industrialist and future old man gives a 2023 TED Talk, which we saw in the February viral video viewable by clicking here.  This quick tease makes the Nietzschean connection again, with Weyland saying to himself, "I am a law only for my kind, I am no law for all." That nugget is, of course, from Thus Spake Zarathustra.

So.  Shout outs to Nietzsche and a date towards which to look.  Judging by the responses online, many a moviegoer was frustrated by the lack of answers and general obliqueness in Prometheus.  As such, this continued viral effort, with its philosophical invocations and ongoing mystery, might just exasperate anybody trying to figure out just what was on the Engineers' minds or suss through some of the other elements of the Alien prequel.

You can see Weyland as an old man who looks kind of like Mr. Peanut in Prometheus, which is currently playing at a theater near you.