Your time and budget probably don't permit you to attend every major event or conference that you'd like. Thankfully, there's a way to virtually attend many of these events - by experiencing them vicariously through the Twitter posts (aka "tweets") of those who are there.
You may recall that I've started using TwInBox, a free Twitter plug-in for Outlook. Regardless of whether you use this tool or the countless other Twitter clients out there, you've probably seen posts that include the # symbol before a word. These are known as hashtags, and they are used to help aggregate posts around a certain topic. (For more on hashtags and getting started with Twitter, review my Twitter 101 post.)
When hashtags are used for events, they create a sort of "back channel" to allow attendees to share what's going on along with short summarys and reactions. It's sort of like the conference hallway conversation, only amplified to a worldwide audience. For instance, this week's Microsoft MIX 10 event for Web developers and designers used the hashtag #MIX10 (and news from the event continues to be shared and discussed with it) so you can use that hashtag to track what happened there even if you couldn't make it to Las Vegas to participate in person.
To subscribe to a hashtag in TwInbox, first click the TwInBox dropdown and select Search/Track/Group. Click New and enter the hashtag you want to track. Optionally, you can enter a new folder for these tweets to be stored (a good idea so you can find them quickly and not have them mixed in with messages from the people you follow). Click Save to start your virtual conference experience!
Hashtags only work when they are consistent (they are simply characters typed into a Twitter client), so if you're planning an event you should try to settle on one early, check that it's not already in common use for something else, and then communicate it to attendees when they register. Twubs.com is a hashtag registry you can use to look up hashtags to either virtually attend events yourself or see if someone else has already claimed the one you want to use.
Advanced move: If you're presenting at an event and want to encourage remote interactions from people who can't be there in person, create a hashtag just for your presentation or panel, publicize it ahead of time to non-attendees (along with the time and timezone of the session), and then have someone monitor it and feed interesting comments and questions from Twitter users outside the room to be read aloud and answered during the presentation.