They're also listing "Doctor Blob's Organism" and "Soup Du Jour" as extras. (http://www.digital-eel.com/) Digital Eel kindly set those (and several other (http://www.digital-eel.com/games.htm) games) free years ago, however I guess this way you can feel like you're paying a token something for them :)
Plus you get a bunch of the Eel's music from the games.
"Weird Worlds" is definitely the star, and this is the cheapest I've ever seen it by a long way, so you should definitely take a look if you've not done so already.
Shadowcat on 7/5/2012 at 17:20 A couple of quick reviews from the Indie Games Blog: