healthfinder
US government site. Useful gateway to respectable American health sites. Fun, easy-to-understand layout, and not squeamish about exciting headlines ("Monkeys cloned by splitting embryos").

NHS Direct
The NHS site. Steady rather than exciting in the determination to be reliable and because it was put together at speed. But already popular. An updated version is on the way.

National Electronic Library for Health
The library will live here, but hasn't moved in yet. The site is taken up with an abstruse conversation between interested parties as to what it should contain.

Patient UK
Provides a long list of patient groups in the UK and abroad. Also lists telephone helplines and patient information leaflets that can be sent for.

US National Library of Medicine: Medline
Medline, the biggest medical database in the world, was set up by the US National Library of Medicine, and is mostly free. Almost any study published by a reputable medical journal will be found here. Medline Plus is more consumer-friendly at same address.

A Doctor in Your House
Cybersurgery - the new spectator sport for the non-squeamish. Watch an operation online if you can bear it.

Contact a Family
Well-presented support network for rare diseases. The charity holds information on 1000 rare disorders and diseases and will put families in touch with each other.

Cancerhelp UK
Very comprehensive cancer information and links on Birmingham University sites, incorporating much material from CancerBacup.

Public Health Laboratory Service
Get your official statistics on flu, meningitis and any other infectious disease you care to name, at the PHLS website.

CyberDocs
A taste of the future. US-trained physicians offer online consultation for $50 to $75 to anybody (almost) anywhere in the world. One of the few sites where doctors will diagnose and prescribe medicines - but they are bound to proliferate before long.