You can't simply copy/paste a Postgres database though...also you'd be surprised how fast SQLite can be...I've used SQLite for projects where I just couldn't get the performance elsewhere. For example, I had a names database with over 100 million rows in it for converting names to diminutives (e.g. David to Dave) and the inverse...after I precomputed a metric ton of indices it went like a rocket. Sure the file was quite big but oh boy was it quick.