These Custom Portal 2 Cores Are Awesome
Portal is definitely a popular series, but not so much that toy manufacturers have started mass-producing Aperture Science playsets. If you want Portal-related figures, you've got to make them yourself. Alternately, you can rely on geniuses like this to make them, and you then you can stare in wonder.
YouTube user Ammnra (who has lots of awesome videos of custom gaming props) has posted a video of his latest triumph: Wheatley and Portal 2's gang of personality cores. I could try to say more, but you should really just check out it for yourself.
The video includes some in-game dialogue, but nothing I'd consider a spoiler (as long as you don't read the comments on the video).