There is a fantastic physics pedagogical (teaching) web site from the US. It's full of Java simulations of important physics theories. It's called PhET.

There is a physicist who is challenging the orthodoxy of complimentarity between particle and waves in quantum physics.

The NPL has a web site dedicated to measuring things called Kay & Laby

Freely available articles on various science subjects can be found at arXiv.org, SLAC, Royal Society and APS.

There are some Richard Feynman video lectures available online.

I can also access the Scientific American online through the OU.

The journal Nature publishes podcasts. Other science related podcasts can be found at nakedscientist.com (not as exciting as it might, at first, sound)

Some nice Hubble Space Telescope desktop backgrounds and some images from science

There are some NASA images at the apollo archive. I found the link at a web site declaring the moon landing a hoax.

Have you ever wondered about snowflakes? Well wonder no longer, instead look on in awe at this great web site devoted to snowflakes.

As a 'freelance scientist', I find the experiments dealing with quantum physics and non-locality to give some of the most mind boggling results in modern science. To see what I mean read Brian Greene's book "The Fabric of the Universe", or look up delayed "choice" quantum eraser on google. Remember these experiments have been performed. You can also read about quantum entanglement. There is quite a varied web site chock full of nick nacks on mathematics or physics. It's on the NASA site. This link takes you to the General Relativity Field Equations section

Greg Egan writes science fiction novels (although he hasn't written a new one for a while) but you can catch up with some java applets etc.

Joddrel Bank Radio obesrvatory have a good introduction to amateur telescopes

The evolution vs creationism debate has a good web site at Talk.Origins

There is a rather entertaining website that skits them gosh darn christians called objectiveministries.org