Slow queries on Views
We recently stumbled on a performance issue on a big project. Loading time was really high on some pages, and we soon came identify a couple of queries slowing down the site. I'd like to show this as a good advice. You shouldn't trust Views + CCK completely when it comes to performance. The popular suite of modules is aimed on softening the process of developing website architecture, so you don't have to write down your queries all the time (and potentially rewrite 2 or 3 times for every change in the project).