This is my development environment for Seaside. One virtual machine (vm1) is for Seaside over Squeak development. I work here most time, forwarding X to my host machine and testing the application by pointing to http://vm1:8080/seaside/myapp. Details here. The second machine (vm0) is for testing integration of my Seaside application on Gemstone/S 64. After loading my app to Gemstone I test the app by pointing to http://vm0:8080/seaside/myapp. Details here. Finally, in my host machine I have Debian GNU/Linux 5.0 amd64 (Lenny) for my every day work (writing docs, hearing music, watching videos, browsing internet, writing blog posts, IM, etc). Also, from my host machine I can fire the stress tools to test either the load capacity or the load balancing of the application. Advantages:

• I start the virtual machines only when I need them.
• My host laptop boot time it is minimal.
• I don’t have to create a 32 bit chroot inside my laptop
• I have a clean 32 bit Debian and a clean 64 bit Debian for other uses
• I can test having the static content in a virtual machine and the application in other and use a proxy to redirect to the correct machine.
• I can test having my application behind a proxy
• I can test load balancing of my servers

Disadvantages:

• More machines to administer
• More configuration and setup involved
• You need a 64 bit machine and a decent amount of RAM and a capable CPU (I have 4GB RAM and a AMD Turion 64 X2 CPU)
• You need to be comfortable administering several machines

But, for me, it works. Maybe it can work for you too.