Roulade allows you to create "tumblelogs" that can aggregate any of your models into one simple list. It was written when I wanted to use jellyroll, but didn't like the idea of defining models for storing roll items, much less the concept of providers - which, for my purposes, was stepping on the toes of the apps that are already in my project anyway. I also wasn't especially thrilled about changing my models to have specific fields just to be jellyroll compatible either. Roulade requires no models of its own, and is flexible enough to follow a non-model based data source if you're into the "provider" thing anyway. However, borrowing a phrase from the jellyroll wiki, "It's also extremely not done yet."
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