LAN boot

I have an old laptop that I would like to use as a thinclient on a network. Hard drive is shot, cdrom is going out and no floppy drive. I am looking for an OS that can boot up and run exclusively from a network(I assume there is some kind of linux distro that does this). Google is not much help or maybe im searching for the wrong thing. I will take anything. Doesn't even need a window manager or anything except maybe text web browser or e-mail client.

you could just use any linux livecd and mount a network drive to save things