Gorgeous Grampa is the fourth limited-time episode promotion to appear in the game this season. Like Gorgeous Grampa, all the others arrived and disappeared very quickly. Here’s what we’ve seen so far:

– The Duff Racer (in September 2012 to promote the first episode)
– Fat Tony (in November 2012 to promote the episode “Penny Wiseguys“)
– The Cool Brown House (also in November 2012 to promote the episode “The Day the Earth Stood Cool“)
– Cool Homer costume (also to promote “The Day the Earth Stood Cool“)

None of these characters, buildings, items and costumes is currently available – and there is no news about whether they’ll be available in the future, even as premium items.

There’ll almost certainly be more free limited-time items to promote episodes in the future. So, that means it’s always a good idea to check for updates a couple of days before any new episode appears in the US.