And galaxies! On thursday my colleague Richard (www.boakes.org) pointed me to http://www.great08challenge.info/ Apparently he studied cosmology before completing his Phd in the Semantic Web and still has an interest in it.
So far I've downloaded the small sets of data. The full set is around 100gb of compressed fits images so will take a while on my rather slow BT connection, not to mention exceed my 30gb cap... I have not looked at the data yet and will need to construct or download a fits viewer.
The general idea from what I have read is to calculate the shear function that has been applied to the image of a galaxy as a result of gravitational lensing from dark matter etc. The desired end result is to be able to construct an accurate map of the dark matter in our universe. Not knowing the original shape of the galaxy or the distribution of matter causing the lensing does make this a rather difficult problem to solve.
As each galaxy image is around 40x40 pixels and you are given thousands of them this would be an ideal problem to solve in a massively parallel way using GPU's and CUDA. Unfortunately I am just too busy with my other projects at the moment but hopefully someone else will feel inspired and take up the challenge!