MrClean 1.8 is an free application that finds and deletes duplicate files, removes empty folders and removes aliases.

I can recommend it if you think you have lots of duplicate files.
Download MrClean v.1.8

Apple has seeded developers with a new version of Mac OS X 10.5.5 (Build 9F9) to test. The latest seed comes just one week after the prior seed.
The newest seed lists 24 new fixes addressed in this seed with a focus on Sync Services, Mail and Addressbook.
Apple has started aggressively seeding Mac OS X builds [...]