Here are 3, which does the job for free:
1) Defraggler (www.piriform.com)
Its recommended to defragment the pc regularly to improve space efficiency. Check out the website for their other cool tool – CCleaner for PC and Networks
2) Find (almost everything) (www.voidtools.com)
It’s website says that it can locate files and folders by name, instantly.
3) Online backup (www.sugarsync.com)
This one offers 5GB free space… now that’s hard to beat.