I can’t tell you where I found this snippet, but it has proven really, really useful. It’s a snippet to create custom post types in bulk, simply by adding a couple of variables to an array. If the code is yours, let me know and I’ll give you credit for it!
I put this code in my functionality plugin which I install on my sites in the mu-plugins folder… that way it’s always available regardless of theme. Putting it in the mu file also means that your plugin won’t get updated by mistake (learned that one the hard way… so give it a good solid unique name… not functionality.php)