Recently, I bought a ThinkPad X60 with Intel Core 2 Duo CPU. Though, I have an external USB CD-Rom, I decided to try PXE installation. I know this long time ago, but never try it out.
In short, you need a DHCP+NFS+tftp server to start. All the tricks are documented here. If you have NAT running on the server, disable it. Otherwise, some funny things happen. PXE installation is not that hard as I thought. Speaking of PXE, I think there is a project about PXE bundle installer. Hope we can see it soon