I currently use my MBP7,1 as my primary computer, running 10.6 and Win7. I would like to switch to OSX Server so I can have a bit more control over the network services and ipfw. is it possible to run OSX Server on a laptop? if so, will anything important or obscure break like VLC, 3D rendering (Steam) or sound devices (external soundcard)?
In my experience, Snow Leopard Server can do everything snow leopard can. Be aware that it doesn't include things like iLife, compared to the workstation build of snow leopard on your laptop which has it bundled. You can install iLife, it just isn't part of the OS install.
I've run MacOSX Server on non-server hardware, although not 10.6 specifically, and not on a laptop.
From what I saw, much of it was just that some things weren't installed; you can easily install command line tools or ipfw on a non-server system.
(although, some of the default kernel parameters are different, eg, max user processes is much lower on client than on server)
... and I can't remember if they changed the dock defaults in 10.6 server ... although iLife isn't installed, they'd still have links to it in the dock, so you'd have a bunch of question mark icons.