Here is a list of the most important tools, websites, and other resources that you can add to your arsenal to make your freelance work a lot easier and more productive. I have compiled them since 2008 and have continued to use them (upgraded of course) in my work and other personal tasks where i find them useful and practical. Most of these tools/websites are for free, some are paid, and some you could get a free trial then reduce down to the free version which is of course limited in functionality. You don't really need to buy these tools if not necessary, but if you think you really need the full, paid version then go for it. Investing on tools that will help you be more productive is a wise decision.

I know you may have also used some tools that which may not have seen on my list. I'd be glad to add them as well as part of the reader contributed tools under our reader recommendations section. Bottom line, lets share and make freelancing life a lot more convenient.

I'll be posting a review on most them soon.

Communication tools:
1. Skype
2. Google Talk
3. Yahoo Messenger

Project Management
1. Teamwork PM
2. Freshbooks
3. Basecamp
4. Paymo

Browser
1. Google Chrome
2. Firefox

Twitter
1. Hootsuite
2. Tweetdeck
3. Seesmic
4. Tweetglide
5. Twellow
6. Listorious
7. Refollow
8. Blastfollow
9. Bit.ly
10. Twitterfeed
11. SocialOomph

Blog
1. WordPress
2. Blogger

Networking
1. LinkedIn
2. Facebook
3. Plaxo
4. Xing

Invoicing
1. Paypal
2. Paypal Outlook Wizard
3. Freshbooks
4. Paymo

Research
1. Mendeley
2. Zotero
3. Google
4. Forrester Research
5. Pubmed
6. Jigsaw
7. Inside Facebook
8. Mashable
9. Wikipedia

Image Source: http://www.artua.com