SpaceSniffer disk usage visualizer
Ever wondered what eats up your disk space? Discovered a nice simple tool which can answer that question. It's called SpaceSniffer and it scans your disk (or a just folder if you want) and then creates a clean map of what takes up space.
One thing to note: I recommend you run it with Administrator privileges. If you don't, it won't be able to scan certain system folders and such.