It's great fun here.
The build system is one of the best I've ever worked with. It's a combination of PVCS (could be any vcs, really) and a number of perl scripts that manage the entire process.
We can also run a single command to build the entire system starting with an empty directory, database and all (creates the tablespaces, everything), generate a zip file, then remotely install that zip file of code on the web and process servers.
Saves a helluva lot of time.