Where I work we frequently use Capistrano1 to deploy our PHP projects. The advent of Capistrano 2 and now a very interesting new web GUI for Capistrano 2 with multi-stage2 looks to have just saved me a good bit of work. Or, in this case, work I was probably never going to get done anyway.
Webistrano is a web based GUI front-end to Capistrano. Capistrano is designed as a command line tool. Capistrano is very much, at it's heart, a remote execution tool to execute commands remotely over SSH on one or many remote target machines. This makes, for example, deploying or gathering information from many hosts at once very trivial and quick. That's good for systems administrators.
Personally, I'm excited about this. I have concerns about the fact that I can't bundle it w/ the PHP applications we deploy without having rails also installed somewhere. But, there's not much to do about that really and I'll go into more about why I care later. All in all I haven't spent much time with this tool yet so I can't really say much more at the moment other than check it out and enjoy. If you have questions there is a thread running in the Capistrano Google Groups, group4.
1. Capistrano - http://www.capify.org
2. Multistage Add-On - http://weblog.jamisbuck.org/2007/7/23/capistrano-multistage
3. Webistrano - http://blog.innerewut.de/webistrano/