Dropbox:
Free for 2GB of storage space.

Beautiful interface, easy to use, cross platform, including an iPhone app and mobile site.
The iphone app is handy for viewing PDFs, but currently only offline syncs the list of documents, not the actual content.
Sharing is easy, but limited to options.  In my case, I want access to other people’s folders ONLY on the website.  I don’t want every change they make to automatically sync to me all the time, eating up resources.

Live Mesh:
Free for 5GB of storage space

As of this review, still in beta.  It provides the ability to sync ANY existing folder you wish, provided it is not a system folder (anything within the Library folder on Mac OSX).
The Live Mesh web interface allows for a lot of flexibility in what you sync to which device.  At the time of my review, the mobile app was not yet available.

For either the above software solutions, you can sync items or folders outside the main sync folders using symbolic links.  I use it to sync my Omnigrafffle stencils and templates across computers.

Ultimately I’ve continued to use Dropbox and have been extremely happy with it.

Researchers at Loughborough University found that it took an average of 64 seconds for a person to recover their train of thought after interruption by email: those who check their email every five minutes waste 8.5 hours a week in this way. “There is no doubt that people use it as an avoidance tactic,” says Yoram Kalman, a post-doctoral researcher in online communication at the Open University of Israel. “The modern office worker works for an average of three minutes before an interruption occurs.”

According to the psychiatrist Edward Hallowell, the stress of trying to process information as rapidly as it arrives is reducing us to quivering wrecks of indecision and demoralisation. As email becomes easier and quicker to use, we are finding it increasingly difficult to sift the relevant information.

http://www.guardian.co.uk/technology/2009/nov/01/email-facebook

As of this date of this posting, here is the full list of the iPhone 3GS Voice Control commands available.  Hopefully as this is adopted, they will roll out more – like finding a contact’s info or initiating an email by speaking the name.

Start Voice Control:
Press and hold the Home button or your headset middle button until the Voice Control screen appears and you hear a beep. 

Cancel Voice Control:
Tap the cancel button on the screen or say “cancel” to close Voice Control.

Call someone in your contacts:
   * call + [name of the person or phone number]
   * dial + [name of the person or phone number]

 If the person has more than one phone number, add:
   * home
   * mobile
   * work
   * other

Make a correction:
   * no
   * nope
   * not that
   * not that one
   * wrong

Music playback:
   * play
   * play music
   * play + album + [name]
   * play + artist + [name]
   * play + playlist + [name] 
   * pause
   * pause music
   * next song
   * previous song
   * shuffle

Music Info:
   * what’s playing
   * what song is this
   * who is this song by
   * who sings this song

Use Genius to play similar songs:
   * Genius
   * play more like this
   * play more songs like this

For best results:
Speak clearly, naturally (like you are making a phone call), pausing slightly so each word is distinct.  Use only iPhone commands and full names or numbers.

http://code.google.com/android/adc/gallery_winners.html

And not being tied to AT&T sure helps, considering they came in DEAD LAST in customer satisfaction in 17 major cities according to:
http://digitaldaily.allthingsd.com/20091201/att-ranked-last-in-consumer-reports-best-cell-phone-service-survey/

http://www.techcrunch.com/2009/12/02/video-time-tablet-magazine/