Sonar is a manuscript submission tracking program, I wrote it because I was going nuts keeping track of short story submissions. This program tells me which market has each story, whether a story has been sold or rejected and which stories are gathering dust instead of earning their keep. If you decide to use it, you will be able to view a list of all your stories and then filter them in various ways (e.g. only show stories which are available to send out). You can add markets, stories and submissions and best of all it's completely free!
If you've ever lent something only to lose it forever (A book, a DVD, tools from the garage and so on) then yLend is for you. You can add a loan in seconds: enter name, item and date and the loan is permanently recorded. When the item comes back, delete the entry!
With BookDB you can enter all your books with author, category, publisher etc and print them out in a variety of formats. Why would you need such a thing? Well, if you're always going to book sales and buying bargains only to get home and find you've doubled up, take a printout with you! BookDB has a super-condensed print mode so you'll need a magnifying glass, but at least it'll save a tree or two.
yWriter is a free novel writing program for authors. It allows you to break your novel into chapters and scenes within chapters. You can reorder scenes using drag and drop, and you can print out a number of reports (summary, synopsis, scene list, work schedule). Gives you a running word count per scene and chapter, and the built-in editor auto-saves your work.