I'm an app junkie and strong advocate of living in the cloud. Here's a list of apps, sites and services I highly recommend using:

Mobile (Android):

• AnyStop - Real-time public transit information.
• CraigsNotifica - Craigslist notifier.
• Dropbox - Accompanying app for Dropbox. 
• Evernote - Accompanying app for Evernote.
• Gtasks - Unofficial Google Tasks for mobile app.
• PdaNet - USB Tethering so that you can use your phone's 3/4G connection. 

Web:

• 750words.com - Daily writers journal. More of my thoughts on this service.
• Disqus.com - Transportable account for commenting on different blogs, forums, etc.
• Dropbox.com - Cloud based storage.
• Evernote.com - Notebook application to capture anything and remember everything.  
• Facebook.com - Social playground.
• Github.com - Public and private code version control repository and project management.
• Gmail.com - Best email service ever.
• Google Reader - Fastest way to consume a ton of content from your favorite spots around the world (wide web).
• Gravatar.com - Email-associated avatar that follows you around.
• KhanAcademy.org - Self-paced, great for digitally going back to school and refreshing your math and science knowlege.
• Lumosity.com - Training the brain through games.
• Mint.com - Money and Bank/Investment/Credit Card Account Mangement.
• OhLife.com - Daily life journal.
• Pandora.com - All internet radio, all the time.
• Posterous.com - Blogging.
• Put.io - Media (torrents, audio, video, etc) fetching and streaming. 
• Quora - Where inquiring minds go when they want to know.
• Songkick.com - Let's you know when your favorite musicians will perform near you. 
• Tumblr.com - Blogging.
• Twitter.com - Thought casting and microblogging.
• Typd.in - Converts roman characters into Japanese Hiragana and Kanji.
• Vimeo.com - Professional Looking Video hosting.
• Youtube.com - All other video hosting.