I don't usually write about apps but there are a bunch out there. On the phone with a couple of consultants talking about how to search through Outlook, Xobni was the recommendation. Google Desktop, too, but that app chews up resources.
Time tracking for freelancers and consultants is a challenge. If you bill by the hour or project, you might want to look at Toggl so that you can remember who to invoice. Then invoice through FreshBooks.
I'm still searching for an automatic back-up app for my laptop to an external hard drive or to DVD. There's a list of back-up apps for Mac, Win and Linux here that I have to research. The one that interests me the most is Bonkey, which is an open-source back-up to Amazon S3. I was pinged on Twitter by CloudBerry about their app, "try CloudBerry Explorer freeware to copy files to Amazon S3".
There's also 24 Killer Apps for your USB flash drive including tools to clean a PC; encryption for your flash drive; and mini/mobile apps for IM, FTP, browsing.
Ever want to edit a PDF but don't want to pay $200+ for Adobe Acrobat? Try Foxit at just $99. Six month trial available.
BTW, did you hear that Kodak has started charging for its photo storage site? And more free SAAS is starting to charge because there aren't enough advertising dollars to support the recurring costs of keeping the service running.