Has your Outlook program become slow and bloated over time? If so, it's not surprising, because as your e-mail store and associated files get larger, Outlook typically takes longer to load, operate, and exit. The problem is that Outlook stores all of your e-mail (and other kinds of data) in a file called a .pst file, and as that file grows, it slows down Outlook. Weight Diet for Outlook ($30, 15-day free trial) helps solve the problem by shrinking your .pst files in a number of different ways.
This program finds and deletes duplicate e-mail messages and unneeded messages such as mail failure notifications, and compresses your .pst file. It also compresses file attachments and moves them out of your .pst file to your hard disk, making your .pst file smaller. To make sure you can still access the files from within Outlook, Weight Diet includes links in the emails where the attachments used to be. You click the links, which then opens the files from where they are stored on your hard disk.
Weight Diet for Outlook works as an add-in from right within Outlook. It's very simple to use, and does its job well. Even without moving my attachments to my hard disk--an option you are allowed to decline--I was able to save more than 150 MB on one .pst file.
If all you want to do is compress your .pst files, you won't need this program, because that can be done from right within Outlook. But if you want to do more than that, and are willing to pay, Weight Diet for Outlook is a great way to shrink your .pst file and speed up Outlook's operations. Note that until you pay for the program, a nag screen appears every time you launch Outlook.