Revision control & dev methods for 1 person project?

I'm working on a social network service that is currently just a 1 person effort (me), and I also do some consulting and programming for others on small web app projects.

I'd like to start using a revision control system to manage these projects, so in addition to rollbacks I also have a better backup of my work, and can at some point add an additional developer (which currently would require hacking my own home-brew workflow).

I'm interested in people's thoughts on RCS systems best suited for projects like these with only one or a few developers.

In the same vein, I'm curious as to people's thoughts on development methodologies for these kind of projects as well- my own workflow comes out kind of cowboy meets agile, but I'd like to start disciplining myself a bit more and have the ability to integrate an additional person when I'm ready.

Tech wise the RCS server needs to run on Linux (Debian), as I will host it on my offsite server which is backed up daily. On the client end I am fully Mac, and currently using a combo of Eclipse, BBEdit and XCode as IDEs, depending on the project, so I need at least command line capability plus Eclipse integration.

thanx!