Over the years I have worked on quite a few projects. This is where I will keep links to the best of them - some are so small that I don't do anything with them.
Ecosystem is a very basic program I wrote in an attempt to model some of the ideas I read about in Sean B. Carroll's book, The Serengeti Rules. It attempts to simulate changing populations of different organisms over time.
ChemKit is a general purpose reaction solver. It aims to be able to estimate reaction products (more information on the way it does this can be found in the blog posts on it) and provide information about the reactions - for example, the Gibb's free energy, entropy changes, and equilibrium constants at different temperatures. It can also calculate different things regarding the elements and make up of different compounds - the % compositions, and the atomic orbital energies for instance.
This is a project that was based on a much older project of mine, ParSi. ParSi was a pretty rubbish particle simulator - you could tell it that a particle was moving at 50m/s from position 0,0 at an angle of 35 degrees and give it an acceleration in a different direction and see what happened.
Unisim was concieved when I was at the National Space Center in Leicester. I was thinking that I could write a program which simulates particles in three dimensions with forces (like gravity, electromagnetism) acting between them. I got gravity working, but eventually I gave up on it after realising that due to the O(n^2) complexity of the algorithm it would take a couple of millenia to do anything too interesting with it.
Intestine was was written in about 2 hours because we were asked to show evidence of Biology revision. It is a very simple simulation thing which shows 6 different particle types (carbohydrates and carbohydrases, proteins and proteases, and lipids and lipases) and shows the rate of reaction between them. It also looks pretty cool. The graph shows rates of reaction, and by fiddling with the initial x and y values and the radius it can also show diffusion. Press 'n' to see the names of the molecules. Not very user friendly, but if you want any help with it just shoot me an email and I will be happy to help.