I've written an introductory page on Matroid Theory, and it's now open. Point your browser to http://www.spectra.net/~zazu/index.htm and look down to the section labeled 'My Research'. The page is written at an introductory level, and anyone with some upper-level undergraduate Mathematics courses -- especially Combinatorics and/or Modern Algebra -- should be able to understand it. At least that's my intention. :)
Matroid Theiry is a rich branch of Combinatorics which in recent years has been the beneficiary of a number of new and important discoveries, and it offers a wide range of topics for research for graduate students. The page has a short introduction to Matroids and the applications of them that I'm studying, and it also has a few references for those of you who might be interested in pursuing the topic in your studies. Hope you like it!