Is it possible to feature posts from one site onto anothers?

What I am looking to achieve is have example.com/b’s most popular posts and recent posts featured on example.com’s homepage.

example.com/b is a different theme entirely than example.com, but I’d like to be able to have the most popular posts and recent posts show up on from /b show up on the top level homepage – example.com

Ideally, I’d like the posts to appear from /b in a tiled gallery layout on example.com and not just in a footer widget. Can this be done and if so how could I go about it?

Thanks!

qubed