I've moved my development environment from my Windows machine to my Mac, which obviously means setting up tools (again). I got the ADT Bundle for Mac from Android Developers, followed the instructions and soon had a nice shiny new install. Then it was time to customise the environment; the first thing I looked at was the Android emulator.
If you're spending any serious time using the Android emulator (and you're on an Intel based machine), you'll want to check out HAXM, Intel's hardware accelerated emulator. The stock emulator is a bit of a snail, to say the least and HAXM vastly outperforms it. This means your "lather, rinse, repeat" cycle when deploying changes is greatly reduced and you're all round more productive. The downside is you have less time staring out of the window, so if you have a particularly nice view you may want to skip this.
I downloaded HAXM via the Android SDK Manager, which resulted in version 1.0.6 being fetched and installed. Unfortunately, running this version of HAXM on my Mac (running Mavericks - 10.9.1) caused the system to freeze, meaning a hard restart was needed.
It seems this is a known issue - see this post on Stack Overflow and this thread on the Intel forums, there's a hot fixed version of HAXM available, which resolved the issue on my machine.
You can download HAXM version 1.0.7 from from the Intel website.