There are some applications which Coda is particularly suited to support. One of those is web serving. If you need to share web pages across several servers, as in a Linux Virtual Server cluster, or if you need extra security, Coda may be just what you need, and its caching could have been designed with web serving in mind. For the same reasons Coda's cousin AFS got its lifetime extended and found new customers. I expect you will need to do some minor programming to support an authenticated web server; it's not ready to go.
Coda may be a good choice wherever you need to share files across several machines, such as in a Beowulf cluster, or across a department or a larger enterprise; this is especially the case where NFS is not an appropriate solution because of its poor functionality and limited performance.
Of course Coda was designed with mobile, disconnected operation in mind, It works well with slow connections, it allows you to connect briefly and update your hoard, then to disconnect and work for hours, then to reconnect again briefly and reintegrate again. I don't know how well it performs with widely separated servers; this is a subject which needs to be investigated. But I can imagine Coda being a useful tool for teleworking, for example.