I'm currently playing around with sbt and as a first experiment I setup a plugin to create a eclipse project from a sbt project.
You can find a version at http://github.com/musk/SbtEclipsify
It is still considered very beta (more likly alpha but it seems to work for me up to now) and keep in mind that I'm new to sbt so any hints, help and constructive criticism is welcome.
I have not a released version yet and the first setup is a little tricky so feel free to ask me if you need help building the plugin.
If everything was setup correctly you have a additional action called "eclipse" which will produce a .project and a .classpath in the project root path. After this you can import the project into Eclipse using Import.. -> Existing Project in Filesystem and choosing the root path. Unless you have a non standard project the project should be ready for editing.
Btw you need to have the scalaplugin for Eclipse installed or else the project will produce errors when imported.
Hope this helps somebody else