I have no idea how the brain works, but it'll start guessing things about you based on your selections (it does this just like a real brain, by turning pink: +2 for pink-flashing brain).
However, brain aside, likebetter doesn't appear to have a mascot: -1 for no mascot.
Then again, there are games you can play with your friends to find out just how good of a friend they are. Consider this a good quarterly tool for reevaluating your relationships (and just in time for holiday gift giving!). I'm learning how well my girlfriend knows me right now...
There are also channels for specific things, like puppies, kittens, bands, and as you may have noticed, even reddit logos.
Bryan was so kind as to create the last one just for us, since I'd always been curious about what the most popular logo doodle was. Maybe we'll make some merch out of it or something, so please vote -- in general, too. Democracy is cool.