[s1k3s]

You don’t actually want that, I think. In practice systems start small, and stuff is added to them gradually. I consider this as a much bigger challenge than designing a “complex” system right from the start. The trick is to be able to keep a system clean over time, not to design it for a year and then just write down the code. So it’s fine to start with your small apps, but instead of throwing it away try to keep adding stuff to it and release more advanced versions say, every month.

That being said, there are a few well known examples of systems that are somewhat complex right from the start. Ecommerce comes to mind: build a configurable ecommerce framework that supports multiple stores, multiple vendors, multiple channels, CC and cash payments, multiple currencies, international delivery etc.