The arrival of "Web 2.0" has forever changed the way we use the internet.  We have transitioned from the web being pages of static content to something far more useful and dynamic.  In addition to the social aspect of the web, this paradigm shift has enabled the development of some truly amazing (and entertaining) web apps.  Here are seven such tools/sites I use often:

1. Google Reader

Google Reader is a web-based RSS feed reader. It allows me to subscribe to recent updates from my favorite websites - currently I have 206 subscriptions! I certainly don't have time to visit 206 websites daily, so I let Google grab all my recent updates, categorize them, and read them at my leisure. If I find an interesting post from a site, I can mark it as a favorite or even share it with friends.

Just recently they've added a feature allowing me to manage my podcast subscriptions for my Android phone. I can add new podcasts from my desktop and they sync directly with my Google Listen app. And once I finish listening to a podcast from my phone, its marked as 'read' in Reader!

2. Grooveshark / Pandora

I don't have my personal music collection with me at work, but I can always fire up Grooveshark to hear virtually any song I want. They have a massive library to choose from and you don't have to buy or download anything. It runs directly in your browser, so no installs needed either. Play a single track, stream an entire album, or build some custom playlists instantly.

Or, if you don't have time to queue up an entire playlist, check out Pandora. You create a new station based on a specific artist/song, and it will automagically play similar music. You can rate the songs it chooses, fine-tuning the type of music it plays. And if you've got the Pandora app on your smartphone, you can listen to your personal, high-def station on the go!

Both sites are ad-supported and free to use. For a small fee, you can upgrade to a premium version that removes the advertisements and provides extra features.

3. media.io

Have you ever needed to convert an audio file to a different format? media.io is a free web-based tool that will do this for you! Simply upload your file (250MB limit), select the desired format and quality, and download the converted version. I've used this a few times to convert some of my .wma files to .mp3 so they'll play on my MP3 player.

4. Stack Overflow and Server Fault

Many people use the web to get answers to their questions. Some people search their questions on Google, and others ask them on sites like Yahoo Answers. But when I have any technical questions, I turn to Stack Overflow for programming issues or Server Fault for server questions. Anybody can sign up to ask/answer questions. The more you participate (espeically with helpful information), the more reputation points you get. And the more points you have, the more you can do on the site. Its a great place for web developers and systems admins to turn to for quick, expert answers and opinions.

5. DNSQuery

When it comes time to deploy a website, it's important to triple-check all the DNS and IP configurations are correct. DNSQuery makes it simple to get detailed information on anything related to domain names, web sites, and servers. No more fumbling around with tricky command prompts. Need to know which IP address a website is hosted on or who the technical contact for a domain name is? If so, check out this great online tool!

6. is[...].com

This is actually a collection of websites that give you a quick answer to your question. Are other people having trouble getting on Twitter? www.istwitterup.com. Should you bring your umbrella to your meeting in Boston? isitraining.in/boston. Can I expect a present from Santa this morning? www.isitchristmas.com. Are you a knight trying to cross the Bridge of Death? whatistheairspeedvelocityofanunladenswallow.com. Some are more useful that others, but overall they give you a quick answer to your simple questions.

7. instant[soundeffecthere].com

There are a growing number of single-purpose sound effect sites that make it simple to play certain effects instantly. Have a big announcement to make? Check out instantdrumroll.com. Are you about to tell a joke? Fire up instantrimshot.com. (Just in case your joke isn't that funny, you may want to have instantcrickets.com open too.) You can find similar sites for everything from sad trombones to emergency yodels to dramatic music clips and more!

Disclaimer: This post highlights some great applications using web 2.0 technologies and ideas. Unleashed Technologies does not represent, guarantee, approve or endorse any third-party website linked to in this post. Please use your own judgement when visiting these external links, as we are not responsible for any content found on these sites.