Using a Macbook Pro to stream music

[KilburnTowers]

....but I actually WANT the screen to go to sleep. I just don't want the CPU to go to sleep.
Ideally, I want:
First choice: to shut the laptop lid and let it continue serving music. InsominaX seems to let me do this but I'm suspicious that it's messing up MinimServer.
Second choice: Let the display go to screensave whilst serving music, even if I can't close it.
Third choice: Let the laptop carry on serving music without going to sleep (Caffeine seems to allow this) but it doesn't seem ideal to leave the display blazing.

p.s. I appreciate this isn't a MinimServer issue, but I'm hoping that one of the MinimServer Mac users would have previously dealt with the problem.