So yeah I ran the Disk Cleanup tool on some of them. We have approx 14 servers with less than 10GB left on the C Drive (which is only the windows install, nothing else all 40GB). Anyway the tool sometimes caused them to have less disk space free after it ran. for example an application server went from having 1.8GB free to having 215mb free after running disk cleanup and the superseded cleanup stated here: http://blogs.technet.com/b/joscon/archive/2011/02/15/how-to-reclaim-space-after-applying-service-pack-1.aspx