#1 Remember the Milk

Without a task manager, most freelancers get overwhelmed very quickly. There's just so much to do when you're running a business - and since you're the sole member of that business, barring any subcontractors who take on excess work, you can't afford to miss a thing. Remember the Milk is a great web-based task manager so you can access it from anywhere.

#2 Echosign

Echosign is hands-down the easiest way to get contracts signed over the Internet. No need to print a contract, sign it and scan it again every time you start a new gig - manage the whole process online on both ends.

#3 Skype

Skype is a great VoIP app that allows you to claim a professional number, make cheap calls locally and abroad, and free calls to other users. It's also got great instant messaging features. No web worker should be without it.

#4 Mailchimp

Mailchimp is the best of the email marketing applications, giving you the tools you need to build an email list, send engaging newsletters and get useful analytics back after each campaign. If you're not using email marketing, you should start today.

#5 TextMate

Everyone needs a good old text editor, and these days, everyone who works online needs to be able to edit a HTML file or even dig into some CSS or WordPress files. TextMate is arguably the best Mac text editor in existence, used by just about every Mac developer who doesn't insist on using Vim for geek cred.

BONUS #6: BrandCrowd

If you need a logo design for one of your clients (or perhaps you're a web designer and you need a cool logo for yourself), try BrandCrowd's logo maker tool!