Calling all die-hard die cutters...

My fabulous huz-band (henceforth he will be referred to as the Gnome on Little Leaf Lane) has been researching die cutters in hopes of finding one that will work with my Mac for cutting out any shape that my heart desires. The Gnome is a very nice one :) Every time in the past two weeks I have ventured the question, "hey what are you doing?" He replies, "looking at cutters." The Gnome has read many a forum trying to figure out what the best combo of software/machine would be for my wants, needs, and desires. I want to be able to design my own shapes on my Mac and be able to cut them out with said die cutter. The Craft Robo looks awesome, but we aren't sure about its compatibility with a Mac. AND what is the difference between the Craft Robo and the Silhouette?...from what we can tell, they seem to be the same machine. The Cricut would be a good option except that you have to drop loads of cash on cartridges and can't design your own shapes (or can you? I would like to know the answer to that question). In other/related news, my Wilton course instructor introduced me to the red, shiny new Cricut Cake the other day. It's fanc-y. Have you seen/heard about it? You can cut out fondant shapes with it...using any existing Cricut cartridges. They are compatible! Can you imagine the number of leaves I could cut out? I would definitely be surrounded in leaves. And you wouldn't be able to see the cake surface for all of the leafy goodness. Oh yeah, back to the die cutters...so I want a die cutter, and I want to use my Mac, and I want to design my own shapes...OH! and be able to cut out any true-type fonts. So crafty blog world...help a sister out! What do I get?