Good News For Open Source Grid" but so far, most of the best grid systems and research have been open source. Activegrid itself is based on LAMP (Linux, Apache, MySQL and PHP/Python). But if you read through the site you will notice that author also thinks LAMP is the best platform for grid.
But the gridmeter brings out some thought provoking information about grid that it a browseble page for those who are interested in grid technology. But the success of grid, so far belongs to open source movement.