Wow, I never expected so many responses! This is a really hoppin' forum. ;p Thanks for all the compliments, guys!
You guys guessed it-- it's a Petco bookshelf aquarium. I swear these things are like betta heaven. I don't think I'll ever have another aquarium with traditional tall proportions ever again, either. It's crazy how much extra usable room their is.
And yep, the plant to the left is bacopa caroliniana. I really like it too! It grows fast to keep the water nice and clean, is super hardy and easy to propagate by trimmings and most all, I think it's really pretty. :)