It´s still beta but maybe worth to take a look at
Besucherring.
The Besucherring is an organisation founded 1949 and offered bus travels to theaters. Today it sells tickets and offers travels around the world.
When my co-workers from Dessau based agency 3undzwanzig and I started the project we found 17 domains - one for every local Besucherring. We decided to merge all these into one domain.
The main problem was to develop a simple to use backend. We used a lot of modules (for venues, for travles, for prices and so on), so the users don´t have to bother where to save a document - MODx will do all this work. Another problem we where confronted with was the amount of data - today we have about 6500 DB entries. Especally for the
travels and the
repertory we had to write custom db queries - Ditto is really fine but in these cases it would need up to 9 seconds to fetch all the data. We are still trying to find a bullet proof solution for cronjobs to clear the db and so to minify the size of the cache file. Almost all snippets and chunks - and there are many of them - we put into external files. This - the cache - is really a caveat for big sites based on MODx and I´m happy to hear that Revolution will bring a more advanced caching system. Nevertheless - our cache file is about 760 kB which is okay for such a big site.
All in all we hope that this website is a proof that with custom tweaks MODx is capable to run bigger websites. All the other agencies who asked for the job offered to use Typo3 - we were the only one who said we will try it with MODx. I hope that somedays it will be the other way round.
Many thanks to the developers and the MODx community.