We've got captioned ones rotating on the main page, on refresh, from Season 1 that were part of a caption contest a while back and I was thinking it's time we got some new ones, hence this appeal.
They can be just Rodney, just Elizabeth, both of them and also team/general ones that look to be interesting for amusing captions. You don't get to caption them yourself - though you can submit captions to the suggestions that get will get voted on - but we give credit to both makers of the graphics and captioners on the site. For more details on specifications and how to submit please check out the news article on Central.
We've got a deadline for this of January 30th just to get the ball moving so we can hold the contests soon.