Freeware: Treesize

TreeSize Free 2.6 Treesize Free shows where the disk space has gone to. It can be started from the context menu of a folder or drive and shows you the size of folders, subfolders and files. Displays also the NTFSRatio (NTFS compression rates).

UltraSearch 1.5UltraSearch searches files on local NTFS drives and provides the results within just a few seconds. No indexing or background process. Use patterns or partial file names and see the results almost while you are typing.