After Grigori Perelman's proof of the Poincaré conjecture and Penny Smith's failed attempt at the Navier-Stokes equation comes another claim that a Millennium problem of the Clay Mathematics Institute has been solved. This time it's the Riemann hypothesis -- and it's a disproof.
Here is the arxiv submission by Tribikram Pati, a respected mathematician from Allahabad. I certainly can't evaluate the paper, but from what I have heard of the author, this must be at least a very serious attempt. According to the Clay Institute rules, even if Prof Pati's attempt is correct, it will need to be published in a peer-reviewed journal and then evaluated by the community over two years (so Perelman, too, needs to wait -- if he's interested at all.)
The Riemann hypothesis was also one of David Hilbert's problems for the twentieth century, and the only one to appear both on his list and on the Clay Institute's.