Recommended minimum spec for a multisite deployment.

Hey all,

Just a bit of a question on a multisite spec point of view.

We've got a VPS up and running but we're wondering what minimum spec you suggest for our Multisite setup.

We are allowing people to sign up for free blogs and we show those blogs on the landing page (using your Network Theme). At this time we have half a dozen sites, but hope when we start to advertise to get many more.

We're using LAMP for our server setup.

Thanks in advance