Just read that IntelliJ IDEA 9 will be split into a Community Edition, and an Ultimate Edition. The Community Edition will be open sourced, and allows the Scala plugin. I’ve been writing Scala code for a few months now, and using IDEA in the office, and TextMate at home. I’m really hoping that I’ll be able to use the open sourced version at home so I don’t have to context switch so much. I’ve tried the Scala plugin for NetBeans, but it is so far off ready, that I prefer using TextMate. I know the scala plugin for IDEA 8.1 works really well, but it doesn’t work in the IDEA 9.0 early access release yet. I hope this gets fixed soon so I can play with scala at home more.
NOTE: I don’t recommend using maven with Scala on the Mac, because it just doesn’t play nicely. Don’t know why, but it’s broken to the point that I no longer even try to use Maven to build my scala code.

Other variant is possible also