Links to check out:

Quickly edit photos (especially for blogs, powerpoints, landing pages) to add perspective, shadows, and reflections without the hassle of Photoshop: [Mac]

Intuitive calculator / notepad / spreadsheet combination app that is way better than the native Calculator app [Mac]

Clone your hard drive for backup/recovery - free and paid options [Mac]

Save and sync files in S3 (up to 2GB free!) - great interface, easy to use, highly recommended [Mac, Windows]